As with the planets list, this list is based on the Star Trek : Encyclopedia but contains some small changes. I have removed those names which are proper names of individuals - for example the empathic 'Gem' from the original series episode "The Empath" has been deleted, as has Data's cat 'Spot'. Also gone are alternate names for species mentioned elsewhere on the list - the Encyclopedia list has an entry for "Ugly Bags Of Mostly Water", the Microbrain name for Humans, but this is redundant since Humans are mentioned under their own name. Finally, Borg species numbers have been moved from their own entries into the description of the individual species where we have names for those (Talaxians, Vulcans, Kazon).
After these changes the list has 741 species listed on it.
Name |
Description | Episode |
| Acamarian1 | Species native to the planet Acamar III. The Acamarian culture is divided into a clan structure; any act of violence towards one member of a clan was considered to be an act against all members of that clan. This led to a great deal of inter-clan warfare which eventually threatened the whole Acamarian society. They were successful in forging peace, but the Gatherer group split off from mainstream culture rather than participate in peace. This changed in 2366 when Captain Picard and Sovereign Marouk managed to convince the Gatherers to return to Acamar.1 | The Vengeance Factor |
| Akaali2 | A primitive humanoid species discovered by Enterprise, the Malurians ran a covert mining facility on the Akaali planet which poisoned the locals.2 | Civilization |
| Akritiri3 | A technically advanced species, the Akritiri were a repressive species who operated an unjust legal system and confined their prisoners in a space station under inhumane conditions.3 | The Chute |
| Aksani4 | Delta quadrant species which took part in a regular sub-warp shuttle race4 | Drive |
| Al-Leyan5 | Probable species name, though this is not certain. Professor Galen planned to travel from Deep Space 4 to Caere IV on board an Al-Leyan transport.5 | The Chase |
| Alcyones6 | People who destroyed the second to last Tarellian plague vessel6 | Haven |
| Aldean7 | Species which were thought to be mythical because they stayed hidden behind a cloaking device for millennia.7 | When the Bough Breaks |
| Aldebaran Serpent8 | Reptilian life form with three heads8 | Hide and Q |
| Aldebaran Shellmouth9 | Creature famous for being tight-lipped. McCoy once compared Spock to an Aldebaran Shellmouth.9 | Amok Time |
| Aldeberan mud leech10 | Species whose secretions acted as a natural sedative. Putting one on your chest and another on your abdomen an hour before going to bed was a cure for insomnia.10 | Anomaly |
| Algolians11 | Humanoid species with golden skin and various ridges on the head. Algolians known for the ceremonial rythms they plan on important occasions.12 An Algolian was present on board the Federation Archaeological Council's annual symposium at Tagus III.13 Some Algolians were to be seen on Deep Space Nine from time to time.14 | Menage a Troi |
| Algorian Mammoth15 | Large creature15 | The Wire |
| Alien Spider | These creatures were native to a planet which Lieutenant Paris and Commnader Tuvok crashlanded on in 2375. They were edible, though somewhat difficult to catch.16 | Gravity |
| Allasomorph17 | This non-corporeal species are capable of assuming any shape at will.17 | The Dauphin |
| Alpha 117 Dog18 | Canine-like creature from the planet Alpha 117. In 2266 one of the creatures was "split" by the Enterprise transporters, malfunctioning as a result of an element from the planet. The attempt to recombine the two creatures succeeded, but the animal died in the process.18 | The Enemy Within |
| Alsuran19 | A Delta Quadrant species which was erased form time by Annorax. Annorax kept some of their foods aboard his Timeship.19 | Year of Hell, Part 1 |
| Altarian marsupial20 | Animal Dr. Phlox used in medicine. Their droppings contained the greatest concentration of regenerative enzymes found anywhere.20 | Broken Bow |
| Altoran21 | A pair of twinned Miradorn claimed to have purchased an artifact from an Altoran trader.21 | Vortex |
| Alvanian Cave Sloth22 | Creature well known for sleeping very soundly22 | The Sword of Kahless |
| Alvanian Spine Mite23 | Small creatures which live in the spines of other beings23 | The Begotten |
| Alvera trees24 | Type of tree which grew on a Kretassian planet. They could live over 300 years and were considered cultural treasures by the Kreetassans.24 | A Night In Sickbay |
| Alverian Dung Beetle25 | Insect known for being unpleasant. In preparing Odo to masquerade as a Klingon, Worf compared him to an Alverian Dung Beetle.25 | Apocalypse Rising |
| Amoeba26 | Single celled life form up to many thousands of miles long26 | The Immunity Syndrome |
| Amphibian27 | Any creature which can live on both land and water27 | Genesis |
| Anaconda28 | Earth snake. Hoshi once saw Anacondas on a nature trip.28 | Fight or Flight |
| Anaphasic life forms29 | Energy creature which lived within a candle flame29 | Sub Rosa |
| Andarians30 | Andarian glass beads were mentioned in this episode, and are presumably manufactured by Andarians.30 | Business as Usual |
| Andorian Amoeba31 | Single celled life form native to Andoria31 | Tuvix |
| Andorians32 | Sentient humanoids with blue skin, white hair and two antennae32 | Journey to Babel |
| Angelian33 | Inhabitants of the planet Angel One, the females are larger and more dominant than the males.33 | Angel One |
| Angosian34 | Prospective Federation members, the Angosians modified their own citizens to make them more militaristic during wartime.34 | The Hunted |
| Ankari35 | Delta quadrant species which assisted the Equinox. The Ankari worshipped nucleogenic life forms from another dimension.35 An Ankari helped Voyager to contact the nucleogenic life forms in 2376.36 | Equinox, Part 1 |
| Annari37 | The Annari are a Delta Quadrant species at war with the Kraylor as of 2377.37 | Nightingale |
| Antarans38 | Species which engaged in several wars with the Denobulans, the last ending around 1853. Over 20 million Antaran casualties resulted from the conflicts. Many Denobulans and Antarans retain a great hatred for one another, and there was virtually no contact between the two species for six generations prior to 2153. During this time there had been some small moves towards greater understanding.38 | The Breach |
| Antarians4 | The Antarians were one of several species which were at war with one another for a hundred years. They presided over a regular race held to commemorate the peace; in 2377 Voayger's Delta Flyer took part in the race.4 | Drive |
| Antedean39 | Piscine species who travel in a dormant state to avoid the stress of space flight.39 | Manhunt |
| Antican40 | Potential Federation members in 2364, the Anticans were from the same system as their enemies, the Selay.40 | Lonely Among Us |
| Apollo41 | A member of an unknown species who considered themselves to be Gods.41 | Who Mourns for Adonais? |
| Arachnid27 | Creature which Barclay de-evolved into27 | Genesis |
| Arbazan42 | Federation member species. An Arbazan ambassador visited Deep Space Nine in 2369. They have a tendancy to take offence easily.42 | The Forsaken |
| Arbazon Vulture43 | A predatory bird. Odo was once exhilarated by the experience of imitating an Arbazon Vulture.43 | The Search, Part 2 |
| Arcadian44 | An Arcadian was present at the hearing which demoted Admiral Kirk back to Captain in 2286.45 | Star Trek IV : The Voyage Home |
| Arcturian46 | Dr. McCoy tried to charter this individual's vessel in 2285 to take him to the Genesis planet.46 | Star Trek III : The Search for Spock |
| Ardanan47 | Species whose elite lived in the floating city of Stratos, while the rest lived worked in mines on the planet.47 | The Cloud Minders |
| Argalan48 | Species from the planet Argala in the Delta Quadrant. The Argalans preferred a cold climate, something the Nyrians found hard to tolerate. At least one Argalan ship was hijacked by the Nyrians.48 | Displaced |
| Argelians49 | Sentient humanoids, native to Argelius II. After a "great awakening" in 2067 the Argelians became highly headonistic, devoting themselves almost entirely to pleasure. Some Argelian women were posessed of mild empathic abilities, although this was largely a lost art by the 2260s.49 | Wolf in the Fold |
| Argosian50 | Sentient species; Sisko once almost got into a fight with one50 | Dax |
| Argrathi51 | The Argrathi punished criminals by implanting the memory of a long prison term into their mind in just a few seconds.51 | Hard Time |
| Arkarian52 | The Arkarians assisted in running the Remmler array. Several of them assisted the terrorist attack on the Enterprise-D.52 | Starship Mine |
| Arkarian Water Fowl52 | Creature noted for its unusual mating habits52 | Starship Mine |
| Arkenite45 | An Arkenite served at Starfleet command during the alien probe emergency of 2286.45 | Star Trek IV : The Voyage Home |
| Arkonians53 | Species encountered by Humanity in 2152. The Arkonians had a reputation for being difficult to deal with, but Captain Archer managed to maintain civil relations with them. They can emit a liquid which is highly effective in healing wounds. They drink a liquid which is poisonous to Humans, and do not handle high temperatures as well as Humans do.54 In 2152 an Arkonian was one of the prisoners aboard the Enolian transport which Captain Archer and Commander Tucker were held on.55 | Dawn |
| Armus56 | Being created when a species learned to transfer their negative feelings into a physical form56 | Skin of Evil |
| Arritheans57 | Delta Quadrant species who engaged in trade with Voyager57 | Revulsion |
| Atrean58 | The home planet of this species underwent severe tectonic activity after the core solidified. The Enterprise-D attempted to re-liquify it in 2370.58 | Inheritance |
| Australopithecine27 | Early hominid which Riker de-evolved into27 | Genesis |
| Axanar28 | The Axanar have a Zymuth gland which releases triglobulin into the blood, a substance similar to Human lymphatic fluid. They are androgynous, and live for over four hundred years. They breathe a nitrogen/oxygen atmosphere and have green blood.28 | Fight or Flight |
| B'omar59 | Highly paranoid, the B'omar tried to place many restrictions on Voyager when it attempted to pass through their space. The Raven was assimilated in B'omar space.59 | The Raven |
| B'Saari60 | The first species to make contact with the Denobulans.60 Native to B'Saari II, the B'Saari are able to reanimate the recently dead - though the process only restores basic body functions. Research into a more complete reanimation was proceeding in 2153.61 | Future Tense |
| Ba'ku62 | Humanoid species who have almost eternal youth thanks to their planet's rings62 | Star Trek : Insurrection |
| Ba'Neth63 | Mysterious and paranoid Delta Quadrant species who are determined to prevent all knowledge of their existence. To this end they frequently cloak both their ships and themselves; the associated image is a residual sensor trace left by a cloaked Ba'Neth.63 | Riddles |
| Bacillus Spray64 | Creature used to attack grapevine parasites64 | All Good Things |
| Bajoran Shrimp65 | Animal native to Bajor.65 | You are Cordially Invited... |
| Bajorans66 | Sentient humanoids native to the planet Bajor66 | Ensign Ro |
| Balduk67 | Possible species name. Worf said he would rather face a Balduk warrior than a child. It may be that the Bladuk are not a species but some social group, so a Balduk warrior may be something like Samurai warrior.67 | New Ground |
| Bamboo68 | Earth plant68 | In the Flesh |
| Bandi69 | The Bandi inhabit the planet Deneb IV, and are a relatively primitive people.69 | Encounter at Farpoint |
| Banean70 | Enemies of the Numiri, the Banea punish murderers by giving them a memory implant which forces them to re-live their crime periodically from the point of view of the victim. The Banea assisted Voyager on its journey back to the alpha quadrant.70 | Ex Post Facto |
| Baneriam Hawk71 | Predatory bird71 | If Wishes Were Horses |
| Bardakian Pronghorn Moose72 | Animal famed for having an exceptionally loud call72 | Unification, Part 1 |
| Bardeezan73 | A Bardeezan merchant ship was suspected of abducting Gul Dukat from Deep Space 9 in 2370.73 | The Maquis, Part 1 |
| Barkonian74 | A primitive species which mistook Data for a native of their planet.74 | Thine Own Self |
| Barolians11 | Species which took part in trade negotiations with the Romulans in 2364.72 The Barolians took delivery of a Vulcan deflector system for the Romulans in 2368.75 | Unification, Part 1 |
| Barrowbug76 | Insect life form native to Bajor. Barrowbugs live in mounds, and swarm forth if the mound is kicked over.76 They are somewhat reminiscent of Earth cockroaches, though they are fist-sized and can spit an acidic venom.77 | Ties of Blood and Water |
| Barzan78 | The Barzan were thought to have the first stable wormhole in their system, but this proved to be only partially true.78 | The Price |
| Bat79 | Flying rodent native to Terra. Similar animals are found on other planets79 | The Reckoning |
| Beauregard80 | Plant cared for by Sulu on the USS Enterprise. Beauregard was about a foot tall and was capable of making a high pitched noise and considerable movement. It reacted badly to the presence of the M113 Creature.80 | The Man Trap |
| Belzoidian Flea81 | Creature familiar to Q81 | Deja Q |
| Benkaran82 | Many Benkarans are sentenced to death for murder by the Nygeans.82 | Repentance |
| Benthan83 | A Benthan was forced to participate in a body swap with Steth.83 | Vis-a-Vis |
| Benzites84 | Sentient humanoids who live in caves84 | Coming of Age |
| Berellians85 | Sentient species known as being poor engineers.85 Jake hustled a Berellian at Dom-Jot.86 | Redemption, Part 2 |
| Berengarian Dragon87 | Reptilian creature which was capable of flying even though they could reach more than 200 metres in length, and which could breathe fire. Discovered in the early 2100s by the Vulcans on Berengaria VII, the existence of the creatures was long doubted.88 Spock saw the dragons of Berengaria VII on one occasion.87 | This Side of Paradise |
| Berserker Cat89 | Felinoid known for having great courage.89 | Let He Who Is Without Sin... |
| Beta Runner Cloud40 | Sentient gaseous being which lived in deep space but was able to posses a Humanoid body40 | Lonely Among Us |
| Beta XII-A Entity90 | Unknown non-corporeal alien which thrived on negative emotions, and used it's powers to promote violence in order to create them.90 | Day of the Dove |
| Betazoids69 | Telepathic humanoids native to Betazed; Federation members69 | Encounter at Farpoint |
| Betelgeusians91 | Federation members native to the planet Betelgeuse II, the Betelgeusians are a humanoid species who evolved from a race of leopard-like eagles. They have claws and bones similar to those of an Earth Condor, though they walk erect.92 | Star Trek : The Motion Picture |
| Bilanan67 | Probable species name for the inhabitants of Bilana III. A Bilanan, Dr. Ja'Dar, developed the Soliton wave drive in 2368.67 | New Ground |
| Bluehorns93 | Animal life form native to the Skagaran planet discovered in the Delphic Expanse by the NX-01 Enterprise.93 | North Star |
| Bok-rat94 | Klingon rodent94 | Soldiers of the Empire |
| Bolians95 | Sentient humanoids with blue skin95 | Allegiance |
| Boraalan96 | Primative species, subject of a prime directive violation by the Captain Picard and the crew of the USS Enterprise crew.96 | Homeward |
| Boranian97 | Probable species name for the people encountered on Boranis III. The species was decimated by an infectious disease as a punishment for resisting the Dominion. Dr. Bashir was able to produce a treatment which would prevent the disease being passed on to the next generation.97 | The Quickening |
| Bore worms98 | Species which lays their eggs in a person's ear.98 | Rogue Planet |
| Borg99 | Powerful species composed of cybernetic humanoids with linked minds99 | Q Who? |
| Borgia Plant80 | Poisonous plant native to planet M-11380 | The Man Trap |
| Boslic100 | A Boslic trader sold Quark the remains of a ship which contained a Jem'Hadar baby.86 | The Abandoned |
| Botha101 | Delta Quadrant life form which used powerful telepathy to attack the crew of the USS Voyager in 2372.101 A member of this species was a drug dealer on a station in the Necrit Expanse.102 | Persistence of Vision |
| Bre'el81 | The Bre'el were threatened when their moon began to fall out of orbit, but were saved by Q.81 | Deja Q |
| Breen103 | Mysterious species who allied with the Dominion during the war with the Alliance103 | Hero Worship |
| Brekkian104 | Humanoid civilisation native to the planet Brekkia. The Brekkians had only one industry, the supply of the narcotic Felicium to the Ornarans.104 | Symbiosis |
| Brenari105 | A telepathic species persecuted by the Devore. A group of Brenari refugees were assisted by Voyager.105 | Counterpoint |
| Brenari105 | Telepathic Delta Quadrant species. Voyager sheltered a dozen Brenari refugees from the Devore Imperium.105 | Counterpoint |
| Bringloidi106 | Oirish Humans who colonised the planet Bringloid V106 | Up The Long Ladder |
| Briori107 | Humanoid species native to the Delta Quadrant107 | The 37's |
| Brunali108 | Delta Quadrant species. The Brunali were decimated by repeated Borg attacks; they infected some of their own people, including Icheb, with a pathogen which could damage the colelctive and deliberately allowed them to be assimilated.108 | Child's Play |
| Bunny Rabbit109 | Earth animal sometimes imagined in the shape of nebula clouds109 | Imaginary Friend |
| Buranian110 | Culture whose pottery resembles both Marlonian and Taguan work.110 | Rascals |
| Bynars111 | Humanoid species who have become highly dependant on computers111 | 11001001 |
| Byzallian112 | Species which was due to hold a cenference on Deep Space Nine in 2371.112 | Defiant |
| Byzatium112 | Spacefaring species. Six Byzatium transports arrived at Deep Space Nine in 2371.112 | Defiant |
| Caatati113 | Humanoid civilization native to the the Delta Quadrant. The Borg destroyed or assimilated most of the Caatati; only a few thousand people survived in 27 refugee ships. Conditions aboard these ships were poor, with food and energy shortages a constant threat. The Caatati took to begging others for supplies, and even on occasion to stealing what they needed.113 | Day of Honor |
| Cairn114 | Telepaths who had never had a spoken language until meeting with the Federation.114 | Dark Page |
| Caitian45 | A Caitian was present at the hearing which demoted Kirk back to Captain in 2286. The fur colourings can include black or brown.45 | Star Trek IV : The Voyage Home |
| Calamarain81 | A mysterious species of energy beings, which Q considered to be intelligent, but flighty. The Calamarain were capable of generating energy fields which they could use to sense the presence of others or attack them at a distance. One Calamarain was considered capable of overwhelming and destroying a Galaxy class starship. Q had tormented the Calamarain, and although he claimed his actions were not all that bad they bore him a considerable grudge. When Q became briefly Human in 2366 a Calamarain attacked the Enterprise-D to get to him for revenge.81 | Deja Q |
| Caldonian78 | A noted race of scholars, the Caldonians attempted to purchase rights to the Barzan wormhole.78 | The Price |
| Caldorian Eel72 | Animal life form which could reach at least four metres in length. Klim Dokachin once discovered a Caldorian Eel on a junked spacecraft and adopted it as a pet.72 | Unification, Part 1 |
| Calrissian Chameleon24 | Animal used in medicine by Dr. Phlox. It's pituitary gland could be made compatible with a dog's. The chameleon secretes a rare toxin which is highly useful in treating respiratory infections.24 | A Night In Sickbay |
| Camorites115 | Humanoid species native to Camor V115 | Bloodlines |
| Canary116 | Earth bird. In ancient times miners would take canaries into tunnels as a way to test for poisonous gas.116 | Harbinger |
| Capellan117 | A fierce but primitive warrior species, the Capellans signed an agreement with the Federation granting them mining rights.117 | Friday's Child |
| Cardassian Vole118 | An animal life form native to Cardassia, the Cardassian Vole is about 25 cm in length, has six limbs and a partial covering of hair. The Voles are a notorious pest aboard Cardassian space stations, damaging as they are attracted to energy fields.119 Quark considered staging Vole fights in his bar for Cardassian patrons, though this was illegal.120 Despite this he and Morn attempted to hold Vole fighting contests on the station, though they were caught before any actual fighting could occur.121 In 2372 Quark made a deal on Vole bellies which netted him a 15% profit margin.122 Quark's bar suffered occasional Vole infestations, much to his annoyance.123 Voles are known for "leaping on one another" with great haste and little preparation when mating.124 The phrase "sick as a vole" was occasionally heard aboard Deep Space Nine.125 Hungry voles are known for having no loyalty.76 | Various Deep Space Nine episodes |
| Cardassians126 | One of the major powers in the Alpha Quadrant, the Cardassians fought a war with the Federation in the past.126 They occupied Bajor for a long period,66 but this was overthrown in 2369.127 They later joined the Dominion128 and as a result suffered greatly during the Dominion war.129 | The Wounded |
| Carlotti102 | A species which are located near to the Necrit expanse. Some Carlotti are involved in criminal activities.102 | Fair Trade |
| Carnivorous Rastipod14 | Large Bajoran creature known for its clumsiness14 | Progress |
| Cat130 | Terran animal noted for its independence.130 Felis Catus is it's taxonomic nomenclature.131 | Data's Day |
| Cave-Rat22 | Cave dwelling animal22 | The Sword of Kahless |
| Ceti Eel132 | Sluglike creature which burrows into a persons ear132 | Star Trek II : The Wrath of Khan |
| Chalnoth95 | An aggressive species, the Chalnoth are anarchists who reject any form of authority.95 | Allegiance |
| Chameloid133 | Shape changing beings once thought to be mythical133 | Star Trek VI : The Undiscovered Country |
| Chessu4 | Species who took part in an annual sub-warp shuttle race4 | Drive |
| Chokuzan134 | A species encountered by Voyager in 2377. First contact occurred when Icheb and Q2 travelled to the Klovari system via a multispacial fissure. A Chokuzan warship, fired on the Delta Flyer with an omicron radiation weapon, injuring Icheb. The Chokuzan was later revealed to be Q, who had disguised himself as part of an effort to test his son's willingness to help others. It is possible that the Chokuzan are an entirely fictional creation of Q.134 | Q2 |
| Chrysallians78 | Species who attempted to buy the Barzan Wormhole78 | The Price |
| Circassian Cat135 | Geordi LaForge owned one of these135 | Violations |
| Coalescent organism136 | This creature killed a Starfleet officer and took command of a subspace relay post.136 | Aquiel |
| Companion137 | An energy cloud, the companion cared for Zefram Cochrane after he disappeared.137 | Metamorphosis |
| Conciousness Parasite138 | Noncorporeal lifeform which attacks a victim just before death138 | Coda |
| Coridanites139 | Beta quadrant species140 which was petitioning for Federation membership in 2257.32 In the mid 2150s, the Coridans were said to manufacture ships even faster and more advanced than Vulcan vessels of the time. However, the Coridan political situation was rather unstable and rebel factions frequently took hostages.141 A Coridantie Ambassador attended the multi-species conference on Earth in 2155.139 | Journey to Babel |
| Corvallen142 | Corvallens ran freighter runs near the Romulan border.142 | Face of the Enemy |
| Corvan Gilvos67 | Stick like animal which is now endangered67 | New Ground |
| Cove Palm143 | Plant which is poisonous143 | Brothers |
| Cravic144 | Now extinct Delta Quadrant species144 | Prototype |
| Crystalline Entity145 | Large spacedwelling lifeform which can destroy life on a planetary scale145 | Datalore |
| Crystilia146 | Flowering plant found on Tele-Marius III146 | In Theory |
| Cyperon Cactus27 | Plant found in the E-D arboretum27 | Genesis |
| Cypriprdium147 | Earth plant147 | Tattoo |
| Cytherian148 | Residents of the centre of the galaxy, the Cytherians bring other species to their space rather than exploring.148 | The N'th Degree |
| D'Arsay149 | Ancient civilisation149 | Masks |
| Dachlyds150 | Picard mediated a dispute involving this species150 | Captain's Holiday |
| Dal'Rok151 | Mysterious creature which periodically threatens a Bajoran village151 | The Storyteller |
| Daliwakan152 | Humanoid species152 | The Cloud |
| Dalvin Hissing Beetle153 | Small beetle which hisses153 | Parallels |
| Dark Matter Lifeform154 | Creature composed of dark matter which Voyager encountered in 2376.154 | Good Shepherd |
| Debrune155 | Ancient offshoot of the Romulans155 | Gambit, Part 1 |
| Deer156 | Animal life form native to Earth. Some Vulcans stranded on the planet once considered eating a Deer to survive.156 | Carbon Creek |
| Degebian Mountain Goat22 | Animal known for its ability to climb22 | The Sword of Kahless |
| Dekendi157 | Species native to Dekendi III.157 | Stigma |
| Deltan158 | Deltans must take an oath of celibacy when serving in Starfleet.158 | Star Trek : The Motion Picture |
| Demerians61 | The ECS Horizon was delivering stromatopod larvae to this species in 2153.61 | Horizon |
| Demons159 | Life form composed of a metallic liquid containing Deuterium159 | Demon |
| Denebian Slime Devil160 | Unpleasant creature once compared to James Kirk160 | The Trouble With Tribbles |
| Denebians161 | Species who dealt with Harcourt Fenton Mudd161 | I, Mudd |
| Denevan Neural Parasite162 | Large single celled organisms which spread from planet to planet causing mass insanity162 | Operation: Annihilate! |
| Denobulan Lemur24 | Highly sought after pet on the planet Denobula. The Lemur is somewhat similar to a dog - it has a tail, fur, and most have one head.24 | A Night In Sickbay |
| Denobulans53 | Intelligent Humanoid species which originated from the planet Denobula20, in the Denobula Triaxa system.163 | Broken Bow |
| Devidian164 | Species which travelled back in time to murder Humans on Earth.164 | Time's Arrow, Part 1 |
| Devore105 | The Devore have a fanatical hatred of all telepaths; within their space, all telepaths were ruthelessley hunted and exterminated. In 2375 Voyager managed to pass through Devore space by hiding their telepathic crew members along with some refugees in transporter stasis.105 | Counterpoint |
| Digger165 | Animal found on Terra Nova.165 | Terra Nova |
| Dikironium Cloud Creature166 | Gaseous life form which feeds on the iron hemoglobin found in Human blood. The creature was capable of altering its molecular structure, enabling it to hide from sensor probes. It was characterized by a sickly-sweet odour. Commander Spock suggested that the creature might exist in a borderline state between matter and energy, with elements of both, and that it may travel by the manipulation of gravity fields, a method he considered extremely efficient. This allowed it to move with incredible speed - when in an atmosphere, it could accelerate and move quickly enough to make it difficult for even a trained security officer to hit it with phaser fire. In space it could travel at high warp speeds. Phasers and even photon torpedoes had no effect on the creature, as its ability to manipulate gravity made it immune to both as well as allowing it to pass through shielding. It is possible that the creature was repelled by radiation, though this is not certain. In 2257 a Dikironium cloud creature was responsible for the deaths of two hundred crew members of the USS Farragut including the commanding officer, Captain Garrovick. In 2268 one of the creatures - possibly the same one - killed several members of the Enterprise crew before being destroyed by an antimatter charge at Tycho IV. Captain Kirk would report his impression that the creature was both intelligent and malevolent, describing it as evil. He also had the impression that Tycho IV was the creature's home planet. Commander Spock suggested that the creature may reproduce by fissioning into thousands of parts.166 | Obsession |
| Dinaali167 | The Dinaali were very short of resources, and rationed healthcare strictly on the basis of an individual's importance to society. In 2377 they acquired Voyager's stolen EMH and employed him in one of their hopitals. The EMH found their method of resource allocation to be unethical, but struggled to find any viable alternative.167 | Critical Care |
| Diomedian Scarlet Moss168 | A form of plant which is difficult to grow.168 | Clues |
| Distortion ring Being169 | Mysterious entity(s) which inhabit a twisted region of space169 | Twisted |
| Dog20 | Terran canine, a popular pet. Captain Archer kept a dog, Porthos.20 | Broken Bow |
| Dolphin28 | Aquatic Earth mammal. Hoshi once went to see dolphins in the wild on Earth.28 The Enterprise-D carried dolphins on board.170 | Fight or Flight |
| Doosodarians171 | Ancient civilisation. The Doosodarians included long pauses called 'Lacunae' in their poetry, and encouraged the audience to experience these by staring blankly at nothing. Some such pauses lasted several days.171 | Interface |
| Doptarians42 | Distant relatives of the Ferengi42 | The Forsaken |
| Dosi172 | Species native to the Gamma Quadrant. The Dosi were members of the Dominion, and traded Tulaberry wine with the Ferengi.172 | Rules of Acquisition |
| Douwd173 | An immortal being of tricks and disguises; a Douwd rendered the Husnock extinct173 | The Survivors |
| Drabidium Calimus110 | Plant similar to a Terran violet110 | Rascals |
| Draco Lizards67 | Flying terran Lizard67 | New Ground |
| Dralian167 | This individual was a thief who stole the EMH from Voyager and sold it to the Dinaali.167 | Critical Care |
| Drathan Puppy Lig174 | Animal sometimes kept as a pet174 | Crossover |
| Draxxan cloud viper175 | Creature which is known for creeping around silently.175 | Doctor's Orders |
| Drayans176 | The physiological changes Drayans experience in old age makes them look very similar to Human children. Drayans once placed great emphasis on developing advanced science and technology, but two generations prior to 2372 they largely abandoned this pursuit in place of a more spiritual philosophy.176 | Innocence |
| Drayjin98 | A large migratory pig-like animal native to Dakala. The females can be aggressive when protecting a nest. Wraiths would sometimes imitate Drayjins to escape being hunted by the Eska. Drayjin meat tastes somewhat like pork.98 | Rogue Planet |
| Dream Species177 | Delta Quadrant species who lived most of their lives in a dream state, communicating with one another and with 'waking species' via telepathy177 At least one member of this species was at the planet Pernaia prime - in a waking state - in 2152 whilst T'Pol, Archer and Mayweather visited.178 | Waking Moments |
| Drella49 | Creature which sustains itself on the emotion of love49 | Wolf in the Fold |
| Dreman179 | Species whose planet was saved from destruction by the Enterprise-D, in violation of the Prime Directive.179 | Pen Pals |
| Druoda180 | Delta Quadrant species who built extremely powerful long range weapons with artificial intelligence systems in control of them. 180 | Warhead |
| Dryworm41 | Giant creature on Antos IV which can produce and use energy without harming itself41 | Who Mourns for Adonais? |
| Earthworm181 | Earth creature which can survive being cut in half.181 | Vox Sola |
| Edo god182 | A powerful transdimensional being or group of beings which cares for the Edo people. Possibly a machine life form of some kind, or possibly biological beings residing in some type of artificial habitat.182 It is also possible that the same being once cared for the Lysians, prompting them to build a space station which closely resembled it, though this is very far from certain.183 | Justice |
| Edosian slugs184 | Animals which were part of Dr. Phlox's medical zoo.184 | The Catwalk |
| Eel-birds9 | Creatures which feel an overwhelming urge to return to the place of their birth in order to reproduce9 | Amok Time |
| Efrosian185 | A Federation member species, Efrosians are identifiable by their characteristic white hair and cranial ridges. An Efrosian was serving aboard the USS Saratoga when it was disabled by the Cetacean probe in 2285.45 An Efrosian held the office of President of the Federation at the time of the Praxis explosion in 2293.133 | Star Trek IV : The Voyage Home |
| Ekosians186 | Species which adopted the Nazi lifestyle after cultural contamination by a Federation scientist.186 | Patterns of Force |
| El-Adrel creature187 | This creature resided on El-Adrel IV. It was only ever partially visible, and only that on occasion.187 | Darmok |
| El-Aurians188 | Civilisation of 'listeners' who were nearly wiped out by the Borg.188 | Star Trek : Generations |
| Elasian189 | A proud warrior species, the Elasians were deadly enemies of the Troyans until a peace treaty in 2268.189 | Elaan of Troyius |
| Elaysian190 | Species which come from a planet that has very low gravity.190 | Melora |
| Ellora62 | Species which was conquered by the So'na and converted into a working class.62 | Star Trek : Insurrection |
| Emergent life form191 | Life form created by the Enterprise-D when it briefly attained sentience191 | Emergence |
| Eminians192 | Species who fought a war with the neighbouring planet Vendikar entirely by computer.192 | A Taste of Armageddon |
| Enaran193 | The Enarans once conducted a genocidal massacre on their planet and attempted to cover up the evidence.193 | Remember |
| Ennis / Nol-Ennis194 | Two groups of people from this species were imprisoned on a Gamma Quadrant moon to fight a permanent conflict as a reminder to the rest of their species of the futility of war. They were known as the Ennis and Nol-Ennis.194 | Battle Lines |
| Enolians55 | Species native to the planet Keto-Enol. The Enolians sent criminals to a prison facility known as Canamar.55 | Canamar |
| Entabens83 | Delta Quadrant species which was highly reluctant to permit ships to enter their space83 | Vis-a-Vis |
| Entharan195 | The Entharans trade extensively with other races, and Voyager tried to buy an isokinetic cannon from them in 2374.195 | Retrospect |
| Eryops196 | Extinct animal species, the last common ancestor of warm and cold blooded life on Earth196 | Distant Origin |
| Eska98 | For nine generations this species went to a rogue planet to hunt the Wraiths.98 | Rogue Planet |
| Etanian197 | Voyager encountered this hostile species in 2373 when Captain Janeway assisted the Nezu to repel Etanian attacks against them.197 | Rise |
| Etanian Order197 | Species native to the Delta Quadrant197 | Rise |
| Evora62 | Species which was accepted as a Federation protectorate despite having discovered warp drive only a year previously.62 | Star Trek : Insurrection |
| Excalbian198 | The Excalbians have no concept of good or evil, and once experimented on Starfleet officers to determine which was stronger.198 | The Savage Curtain |
| Exocomp199 | Artificial life forms199 | The Quality of Life |
| Fabrini200 | Many Fabrini travelled through space for centuries in the giant asteroid vessel Yonada.200 | For the World is Hollow and I Have Touched the Sky |
| Fargan157 | Animal life form native to Dekendi III. Mayweather described them as looking somewhat like cows with humps.157 | Stigma |
| Farians201 | A Humanoid species native to Farius Prime. The Farians are known for haveing a high rate of criminal activity; the Orion Syndicate is highly active on Farius Prime. A cosmopolitan world, many aliens species are to be found on the planet. The Farians use public transportation systems and paper currency, and is home to a Klingon Embassy. In 2374 Miles O'Brien carried out a covert mission on Farius Prime, penetrating an Orion Syndicate network.201 | Honor Among Thieves |
| Farn202 | Humanoid civilisation native to the Delta Quadrant. Some were assimilated by the Borg202 | Unity |
| Farpoint Station69 | Form assumed by a large shapeshifting space based lifeform when it was injured69 | Encounter at Farpoint |
| Felaran Rose203 | Plant found on a planet in the Delta Quadrant203 | Parturition |
| Ferengi204 | Alpha Quadrant species who are largely motivated by avarice204 | The Last Outpost |
| Fire Ants3 | Poisonous insect native to Terra3 | The Chute |
| Fire Beast of Sullus176 | Creature from the myths of the Drayos176 | Innocence |
| Fire Snakes102 | Reptile species102 | Fair Trade |
| Fire wolves98 | Animal life form which lived on Dakala, a rogue planet encountered by the NX-01 Enterprise in 2151.98 | Rogue Planet |
| Flaxians205 | A member of this species visited Deep Space Nine in 2371.205 | Improbable Cause |
| Flitter Bird206 | Avians native to Rhymus Major206 | Profit and Loss |
| Folnar Jewel Plant114 | Plant which produces a resin which sets to form a gemstone114 | Dark Page |
| Founders207 | Shapeshifting liquid species native to the gamma Quadrant207 | The Search, Part 1 |
| Frunalian127 | Alpha Quadrant species127 | Emissary |
| Gagh11 | Serpent worms.208 | A Matter of Honor |
| Galipotans15 | Civilisation which does not acknowledge the concept of time. They also make very good sweaters.15 | The Wire |
| Gallamite73 | Species famed for having transparent skulls. Dax once dated a Gallamite73 | The Maquis, Part 1 |
| Gamelan209 | The Enterprise-D once helped the Gamelan by piloting an old freighter carrying nuclear waste away from their planet.209 | Final Mission |
| Garanian Bolites210 | Small creatures which cause intense itching and extreme skin colour changes when they bite210 | A Man Alone |
| Garden snake211 | Animal life form to be found on Earth.211 | Similitude |
| Garenor19 | Species erased from history by Arronax.19 | Year of Hell, Part 1 |
| Garili Tree212 | Plant found on the Vhnori home world212 | Emanations |
| Garlanic Tree190 | Plant native to the Elaysian home planet190 | Melora |
| Garren213 | A group of Garren miners became infected with the Macrovirus, and were killed by the Tak Tak to prevent the spread of the disease.213 A Garren trader attempted to steal the Druoda warhead from Voyager in 2375.180 | Macrocosm |
| Gatherers1 | Nomadic people who split off from the Acamarians; they have now been reabsorbed1 | The Vengeance Factor |
| Gavarian214 | Porbable species name. A Gavarian ship was scanned by some Ferengi in the 2150s.214 | Acquisition |
| Gideons215 | The planet Gideon suffered from massive over population, which they hoped to cure by spreading disease.215 | The Mark of Gideon |
| Glob fly216 | Insect known for being very small, completely harmless, and extremely irritating216 | The Outrageous Okona |
| Golanans217 | Technologically advanced Alpha Quadrant civilisation who died out approximately 1,000 years ago217 | Prodigal Daughter |
| Gomtuu218 | One of a species of organic spacecraft which once numbered in the millions218 | Tin Man |
| Gorgan219 | Noncorporeal lifeform which killed the adults of the Starnes Expedition219 | And the Children Shall Lead |
| Gorn220 | Immensely strong reptilian species which once attacked a Federation outpost220 | Arena |
| Gorokian Midwife Toad221 | Animal life form221 | Death Wish |
| Grazerite222 | A Federation member species. The Federation President in 2372 was a Grazerite.222 | Homefront |
| Gree223 | Species native to the Delta Quadrant223 | Elogium |
| Grisella224 | Species which hibernates for long periods224 | The Ensigns of Command |
| Gulgallian Rat84 | Creature which scared Wesley Crusher84 | Coming of Age |
| Gunji Jackdaw71 | Bird similar to a Terran Ostrich71 | If Wishes Were Horses |
| Haakonians225 | Humanoid species from the Delta Quadrant225 | Jetrel |
| Hadrosaur196 | Terran cretaceous dinosaur, ancestor of the Voth196 | Distant Origin |
| Halanans226 | Species who can project telepathic images, sometimes unconsciously. Halanans mate for life, and would rather die than break up a marriage.226 | Second Sight |
| Haliian136 | Haliians are moderately telepathic.136 | Aquiel |
| Halkans227 | Pacifist species who refused to sell dilithium to the federation in case it was used for war.227 | Mirror, Mirror |
| Hanonian Land Eel228 | Large carnivore native to Hanon IV228 | Basics, Part 1 |
| Hara cat229 | Life form native to the Bajoran system229 | Second Skin |
| Haradin230 | Species to be found in the Delphic Expanse in the 21st/22nd century.230 | E2 |
| Harkonian231 | Delta Quadrant species. A Harkonian woman sold the shuttle Alice to Avidon231 | Alice |
| Havenite6 | Residents of the planet Haven, which is claimed to have mystical healing powers.6 | Haven |
| Hawk232 | Bird native to Earth. Captain Janeway once suggested to the holographic Leonardo DaVinci that he model his flying machine on the Hawk.232 | Concerning Flight |
| Hazari233 | An advanced, violent, ruthlessly efficient bounty hunter species which was unwittingly employed by the Think Tank to capture Voyager. Known to the Borg as Species 4228, they make excellent tactical drones 233 | Think Tank |
| Hekaran234 | Species which discovered the damaging effect warp drive had on the fabric of space.234 | Force of Nature |
| Hierarchy235 | Technologically advanced Delta Quadrant species who are heavily reliant on bureaucracy235 | Tinker, Tenor, Doctor, Spy |
| Hill People236 | Primitive hunter-gatherers who warred with the Village People236 | A Private Little War |
| Hirogen237 | Technologically advanced species dedicated to hunting237 | Hunters |
| Horta238 | Rock creature which looks like a Pizza238 | The Devil in the Dark |
| Humans239 | Powerful Alpha Quadrant species239; Borg designation Species 5618240 | The Cage |
| Humpback Whale45 | Species of whale native to Earth; hunted to extinction in the past, now repopulated via time travel45 | Star Trek IV : The Voyage Home |
| humuhumunukunukuapua'a110 | Terran fish110 | Rascals |
| Hunters241 | Species native to the Gamma Quadrant who hunt the Tosk241 | Captive Pursuit |
| Hupyrians242 | Species known for their devotion to those who employ them242 | The Nagus |
| Hur'q22 | A species which conquered the Klingon homeworld, Qo'noS (Kronos) about 1,000 years prior to The Next Generation. Their name is the Klingon word for "outsider" and is probably not their own name for themselves. The hur'q plundered Qo'noS, stealing the revered Sword of Kahless. They apparently originated in the Gamma Quadrant, and may have travelled through the Bajoran Wormhole to reach our part of the galaxy.22 | The Sword of Kahless |
| Husnock173 | A species of 'hideous intelligence', rendered extinct by a Douwd173 | The Survivors |
| Ice Bores243 | Species of worm which lives on Andoria. Ice bores tunnel through the ice by generating very high temperatures; it can be very dangerous to encounter a swarm of them unexpectedly.243 | The Aenar |
| Iconians244 | Ancient and highly advanced species now extinct244 | Contagion |
| Idanian245 | Odo once became romantically involved with an Idanian secret operative.245 | A Simple Investigation |
| Iguana27 | Terran reptile.27 A member of the USS Enterprise crew was turned into an Iguana by Charlie in in 2266.246 They where later turned back to human form by Charlies adoptive parents. | Genesis |
| Ikaaran230 | Species to be found in the Delphic Expanse in the 21st/22nd century.230 | E2 |
| Ilari247 | Voyager became involved in an Ilari civil war when the leader of a dissident faction transferred his personality into the body of Kes.247 | Warlord |
| Ilidarians248 | Delta Quadrant civilisation248 | Cathexis |
| Illyrians249 | Species native to the Delphic Expanse. Archer raided an Illyrian ship in 2153 in order to steal a warp coil to repair Enterprise's drive, leaving them with a three year trip home.249 | Damage |
| Imhotep4 | Delta quadrant society who took part in a regular sub-warp shuttle race4 | Drive |
| Immunocytic Gel Worms20 | Animal used by Dr. Phlox.20 | Broken Bow |
| Interphasic Organisms250 | Parasitical life forms which infested the Enterprise D250 | Phantasms |
| Iothra190 | Species which breathes hydrogen190 | Melora |
| Iotians251 | Highly imitative species who based their lives on earth gangsters after a visit from a federation starship.251 | A Piece of the Action |
| Isis252 | Life form of unknown origin, apparently a shapeshifter252 | Assignment: Earth |
| Ithenites253 | Species which were Federation members in 2554.253 | Azati Prime |
| Iyaaran254 | Species which visited the Enterprise-D in 2370. The Iyaarans had no concepts of crime, pleasure, antagonism or love and used their visit to try and provoke some of these in the Enterprise crew. Iyaarans reproduce by post-cellular compounding, and emerge from the natal pod fully grown. There are therefore no children in their species.254 | Liaisons |
| J'Naii255 | Humanoid species who denied the concept of gender255 | The Outcast |
| Jarada256 | Insectoid civilisation who are fanatical about etiquette256 | The Big Goodbye |
| Jem'Hadar207 | Genetically engineered species created as soldiers for the Dominion207 | The Search, Part 1 |
| Joranian Ostrich257 | Life form known for dipping its head under water when threatened, often until it drowns257 | Past Prologue |
| Kadi258 | Delta Quadrant species encountered by Voyager in 2375.258 | Someone to Watch Over Me |
| Kaelon259 | The Kaelons volunteer for suicide at the age of 60 in a ceremony called 'The Resolution'.259 | Half a Life |
| Kalandans260 | People who built an artificial planet, but were killed off by a disease260 | That Which Survives |
| Kantareans261 | Likely name of the species encountered by the NX-01 Enterprise in 2152. The species is not named, but their home planet of Kantare is; Trek naming convention usually names the species after the planet.261 | Oasis |
| Karemma172 | Gamma Quadrant civilisation known as traders172 | Rules of Acquisition |
| Kartelans262 | Species from whom Voyager purchased 12 kilos of Amber Spice262 | The Voyager Conspiracy |
| Kataanians263 | Species extinct for some 1,000 years.263 | The Inner Light |
| Kavarian tiger-bat264 | Animal from the planet Kavaria264 | For the Cause |
| Kayrilllian Eel225 | Creature native to the Delta Quadrant. Being immersed in a pit of Kayrilllian eels would be a highly unpleasant experience.225 | Jetrel |
| Kazleti265 | Probable species name. Voyager crewmember Chell wore a necklace of Kazleti design.265 | Learning Curve |
| Kazon266 | Humanoid Delta Quadrant civilisation266; deemed unworthy of assimilation by the Borg. Borg designation Species 329267 | Caretaker, Part 1 |
| Kellerun268 | Species which helped to create the Harvester weapons, then tried to erase all knowledge of them after the war they were made for ended.268 | Armageddon Game |
| Kelvans269 | Species from the Andromeda galaxy269 | By Any Other Name |
| Kerelian270 | Species known for its highly sensitive hearing270 | Lessons |
| Kes271 | People from the planet Kesprytt III who applied for Federation membership271 | Attached |
| Kesat63 | The Kesat thought the Ba'Neth were mythical until Voyager helped an investigator to track them down. 63 | Riddles |
| Kesprytt271 | Paranoid species, some of which petitioned for Federation membership.271 | Attached |
| Khefkan272 | Species from the planet Khefkan IV.272 | Invasive Procedures |
| Kinbori273 | Delta Quadrant people whom Voyager encountered in 2376 at the Markonian outpost.273 | Survival Instinct |
| Klabnian Eel13 | Species which Q did not like13 | Qpid |
| Klaestron50 | Curzon Dax once worked on the planet Klaestron, where he had an affair with the wife of a local leader.50 The Klaestrons once developed an incredibly effective treatment for burns.229 | Dax |
| Klingons274 | Major species native to the Alpha and Beta Quadrants274 | Errand of Mercy |
| Kmada275 | Delta Quadrant species. Eight months and seventeen days prior to Stardate 52586.3 the Kmada attempted to sabotage the life-support systems of a duplicate of Voyager using low-frequency theta radiation.275 | Course: Oblivion |
| Kobali276 | Species which reproduces by scavenging the dead of others and reanimating them.276 | Ashes to Ashes |
| Kobheerians118 | A Kobheerian freighter brought Amin Marritza to Deep Space Nine in 2369.277 In 2371 Commander Sisko impersonated a Kobheerian in an attempt to bluff his way into Cardassian space.229 | Duet |
| Kobliad278 | Species which was dying out and required Deuridium to prolong their lives; despite locating new sources in the Gamma Quadrant, there was not enough of the substance for the whole population and some Kobliad took to stealing shipments. A Kobliad criminal once took over the body of Dr. Bashir whilst on the run.278 | The Passenger |
| Kohl279 | Delta quadrant which was nearly went into a virtual reality environment to shelter from a disaster but were terrorised by their own worst nightmare.279 | The Thaw |
| Kohms280 | Humanoid residents of Omega IV280 | The Omega Glory |
| Koinonian281 | An ancient Koinonian mine killed Enterprise-D crewmember Marla Aster.281 | The Bonding |
| Kolar Beast62 | Klingon animal62 | Star Trek : Insurrection |
| Kolarin282 | Pre-warp civilisation located near to the Romulan border. B-4 was discovered on the Kolarin homeworld.282 | Star Trek : Nemesis |
| Kolhari262 | Delta quadrant species which uses tetrion based power cells262 | The Voyager Conspiracy |
| Komar248 | A Delta Quadrant species, the Komar are trianic energy beings who live in a dark matter nebula.248 | Cathexis |
| Kostolain283 | Species which had rigid rules regarding protocol. Lwaxana Troi almost married the Kostolain Minister Campio in 2368.283 | Cost of Living |
| Kovaalans230 | Aggressive species which inhabited the Delphic Expanse. The Kovaalans would routinely attack any ship which infringed on their territory.230 | E2 |
| Kradin284 | Species which was engaged in a vicious war with the Vori.284 | Nemesis |
| Kraylor37 | Species which was engaged in a war with the Annari as of 2377.37 | Nightingale |
| Kreetassans53 | Species first contacted by the NX-01 in 2152. The Kreetassan language is highly complex, with most of the words having many different meanings depending on the context in which they are used. Eating is considered a very delicate matter by the Kreetassans - their word for eating is the same one used for mating, and both activities are expected to be carried out in private. The first contact ended abruptly when the NX-01 crew offended the Kreetassans by inviting them to share a meal.181 Captain Archer again offended the Kreetassans on a visit to their home world when Porthos relieved himself on some highly valued sacred trees. Archer was in turn offended that the Kreetassans failed to inform him that their planet harboured diseases dangerous to Porthos. He eventually decided to accept their oversight and managed to make amends for his own slight by performing a ritual of apology in front of the Kreetassans.24 A Kreetassan was present on Pernaia prime when Archer, T'Pol and Mayweather visited it in 2152.178 | Vox Sola |
| Krellans201 | Civilisation whose food was popular with other planets, especially Farius Prime201 | Honor Among Thieves |
| Krenim19 | Delta Quadrant civilisation who used temporal weaponry in some timelines.19 | Year of Hell, Part 1 |
| Kressari285 | Reptilian species known for trading in plant DNA. At least some Kressari also ran weapons from the Cardassians to the Bajoran terrorist group known as The Circle.285 | The Circle |
| Kriosians170 | Humanoid species native to Krios system, had along running conflict with the Valtese.170 | The Perfect Mate |
| Kryonian Tiger109 | Creature found in the Brentalia Zoo109 | Imaginary Friend |
| Ktarians286 | Species which attempted to subvert Starfleet via an addictive game286; Borg designation Species 6961287 | The Game |
| Kyrians288 | A species which in the distant future will come to believe that Voyager once engaged in a brutal war against them.288 | Living Witness |
| L-S VI Life-form289 | Entity discovered by Dr. Mora Pol289 | The Alternate |
| Lapling290 | Highly endangered species; the last surviving member was owned by Kivas Fajo.290 | The Most Toys |
| Lavaflies213 | Insect lifeform of large size, native to Talax213 | Macrocosm |
| LB10445291 | Single celled life form291 | Time's Arrow, Part 2 |
| Leaf Miners64 | Parasites often found on grape vines64 | All Good Things |
| Ledosian292 | Delta Quadrant species which had strict rules regarding traffic around their space stations. An area of their home world was covered by a force field set up in the distant past by an unknown people, possibly Species 312. The Ventu people lived within the forcefield, which was apparently designed to prevent the Ledosians from offering them the benefits of modern technology.292 | Natural Law |
| Legarans293 | Species who live within a deep layer of mud293 | Sarek |
| Lemur27 | Small primate which Picard began to de-evolve into27 | Genesis |
| Lenarians294 | Species who are not fond of the Federation294 | Tapestry |
| Lethean22 | The Letheans are able to inflict devastating telepathic attacks on others.22 | The Sword of Kahless |
| Leyrons295 | Species who use gestures for non-verbal communication295 | Loud as a Whisper |
| Ligonian296 | Highly honour-bound, the Ligonians produced the vaccine which was used to treat the Anghalese fever in 2364.296 | Code of Honor |
| Ligorian Mastodon297 | Large but stealthy animal297 | Blaze of Glory |
| Lissepians118 | Spacefaring civilisation. A Lissepian captain once traded self sealing stem bolts for 5,000 wrappings of Cardassian Yamok sauce.14 | Progress |
| Lokirrim298 | The Lokirrim were engaged in a war with holographic lifeforms, and destroyed all Holograms on sight.298 | Body and Soul |
| Loon297 | Bird native to Earth297 | Blaze of Glory |
| Loque'eque299 | Species native to the Delphic Expanse. The Loque'eque became extinct several centuries prior to 2153; they created a virus which would convert those it infected into replicas of their own species in an attempt to keep their race alive. The appearence of these replicas is the only remaining record of the appearence of the Loque'eque.299 | Extinction |
| Lothra190 | Hydrogen breathing sentient life form. Dax knew a Lothra who was in love with an Oxygene despite the fact that they could only spend 40 minutes a day in the same environment.190 | Melora |
| Lumerian300 | The Lumerians are capable of transferring their negative emotions onto others.300 | Man of the People |
| Lurians301 | Humanoid civilisation with two stomachs and multiple hearts. Morn is a Lurian301 | Who Mourns for Morn? |
| Lurillian20 | Before the age of four this species can only breathe methyl oxide. They must then be weaned to an oxygen/nitrogen mix.20 | Broken Bow |
| Lycosa Tarantula302 | Spider; Miles O'Brien had a Lycosa Tarantula for a pet302 | Realm of Fear |
| Lynars303 | Batlike creature which lives on Celtris III303 | Chain of Command, Part 1 |
| Lysians183 | Species which were at war with the Satarrans as of 2368. The Lysians were far behind the Federation in weapons technology, and the Satarrans used a mind altering technology to fool the Enterprise-D crew into attacking them.183 The Lysian central command complex closely resembles the Edo god, and it is therefore a possibility that the Lysians were also involved with this being at some time in the past.182 | Conundrum |
| Lyssarian desevae211 | Animal life form. The epidermal layer of the desevae secretes a viral suppressant useful as a salve for cuts and bruises. When implanted with DNA from a donor species it exactly replicates that species' life cycle, becoming a perfect duplicate. However, the clone goes through the life cycle at an extremely accelerated pace, being born, growing old and dying in approximately 15 days. The Lyssarians call these creatures Mimetic Simbiots, and as of 2154 their existence was a very closely guarded secret.211 | Similitude |
| Lyssarians211 | Species which used the Lyssarian desevae to make clones.211 | Similitude |
| Lytasians304 | Civilisation who once warred with the Ferengi304 | The Magnificent Ferengi |
| M'klexa305 | Species which visited the planet Valakis prior to the NX-01 Enterprise's visit of 2151.305 | Dear Doctor |
| M-113 Creature80 | Creature which needed regular doses of salt to live and was able to project false images of itself to others.80 | The Man Trap |
| Macrovirus213 | Virus which grows up to a metre across and can defy gravity213 | Macrocosm |
| Makers161 | Ancient civilisation which created advanced androids later controlled by Harry Mudd161 | I, Mudd |
| Malcorian306 | A pre-warp species, the Malcorians were contacted by the Federation but eventually declined the offer of friendship.306 | First Contact |
| Malkoth19 | A Delta Quadrant species erased from time by Annorax. He kept a bottle of their spirits on his ship, the only one remaining in the universe.19 | Year of Hell, Part 1 |
| Malon307 | Species which pollutes the galaxy with radioactive waste307 | Night |
| Malosian308 | Traders who operated in the Delphic Expanse. This race may be ficticious, as Archer mentioned them as part of a plot to trick Degra into revealing details of the Xindi weapon program.308 | Stratagem |
| Malurian309 | Beta Quadrant310 species which mined minerals from the Akaali home world in 2151, poisoning the natives in the process. Their operation was stopped when the NX-01 intervened.2 The Malurian species was destroyed in 2267 when the Nomad probe sterilised their system.309 | The Changeling |
| Manchovites30 | Civilization which were engaged in a war at some point in the 24th century. Gaila and Hagath sold the Manchovites 150,000 hand weapons. They also sold 100,000 of the same weapons to their enemies, thus profiting from both sides of the war. The arms dealers were annoyed when an armistice was subsequently signed.30 | Business as Usual |
| Maple Trees68 | Earth plant68 | In the Flesh |
| Mari311 | Telepathic civilisation in the Delta Quadrant who have largely eliminated crime311 | Random Thoughts |
| Marijne VII Beings171 | Sentient beings encountered by the Enterprise-D which communicated by directly accessing one anothers thoughts. The beings lived in subspace.171 | Interface |
| Markalians118 | The Markalians are a species seen on Deep Space Nine occasionally.118 Some Markalians are notorious for their smuggling and other criminal activities; Odo arrested one on Deep Space Nine during the Federation's takeover of the station.127 Some Markalians fine employed as mercenaries.278 Kassidy Yates employed a Markalian on the Xhosa.264 A wounded Markalian was being cared for in the field hospital on Ajilon Prime when Jake visited312, and at least one was interned by the Dominion in the run up to the Dominion war.313 In 2374 Molly O'Brien wounded a Markalian in Quark's Bar.314 | Various Deep Space Nine episodes |
| Markoffian Sea Lizard81 | Life form familiar to Q81 | Deja Q |
| Marlonian110 | Culture whose pottery resembles both Buranian and Taguan work.110 | Rascals |
| Mathenites229 | Possible species name. Legate Ghemor said that the Mathenite government had offered him political sanctuary.229 | Second Skin |
| Mawasi19 | Delta Quadrant civilisation; in an alternate timeline the Mawasi allied with Voyager against the Krenim19 | Year of Hell, Part 1 |
| Mazarite315 | The Mazarites had a corrupt government in the 2150s, which they were trying to correct with Vulcan help.315 | Fallen Hero |
| Medusan316 | This is actually a Medusan travelling box. For safety reasons we cannot show you an actual Medusan.316 | Is There in Truth no Beauty? |
| Megarite158 | Approximately Humanoid species158 | Star Trek : The Motion Picture |
| Melkotian317 | Powerful telepaths, the Melkotians do not like outsiders but were eventually persuaded to make contact with the Federation.317 | Spectre of the Gun |
| Mellitus49 | Creature which is solid when still and gaseous when moving49 | Wolf in the Fold |
| Melvaran mud flea55 | Animal life form.55 | Canamar |
| Memory Virus318 | Organisms that ate peptides within the hosts brain318 | Flashback |
| Menk305 | A primitive species which shared the same planet as the Valakians. The Menk were immune to the disease which threatened the Valakians.305 | Dear Doctor |
| Menthar319 | Civilisation which fought the Promellians to their mutual annihilation319 | Booby Trap |
| Meridians320 | Species who's planet shifted In the alternate dimension they existed in a non-corporeal state.320 | Meridian |
| Metalic Microbes321 | Fossilised examples of these life forms were discovered within a graviton ellipse321 | One Small Step |
| Metrones220 | A highly advanced species, the Metrones staged a contest between Kirk and a Gorn starship captain.220 | Arena |
| Microbiotic Colony208 | Subatomic life form which eats away at metals208 | A Matter of Honor |
| Microbrain322 | An inorganic life form native to Velara III.322 | Home Soil |
| Microvirus1 | Artificially created organism1 | The Vengeance Factor |
| Mikhal Traveller323 | This largely nomadic race love to travel the galaxy in small craft, swapping tall tales with one another.323 | Darkling |
| Mikulaks324 | Civilisation who donated tissue samples to study Correllium fever324 | Hollow Pursuits |
| Minnobia30 | Civilisation. During his time as an arms dealer Quark falsely informed Hagath that he couldn't supply him with a mutagenic retrovirus because he had sold it all to the Minnobia for use in their war against the Vek.30 | Business as Usual |
| Mintakans325 | These primitive Vulcanoids suffered cultural contamination from an accidental first contact with the Federation.325 | Who Watches The Watchers? |
| Miradorn21 | The Miradorn are born in twinned pairs, with an extremely strong bond between each twin. 21 | Vortex |
| Mislan326 | Species from the planet Mislan. Voyager encountered a Mislan ship which had been destroyed by the Swarm in 2373.326 | The Swarm |
| Mizarian95 | Mizarians value peace above all else, and as a result have been conquered six times in the last three hundred years. 95 | Allegiance |
| Mokra327 | Species which lived under paranoid, tyrannical rulers.327 | Resistance |
| Monean328 | Species which populated the space ocean.328 | Thirty Days |
| Mordanian329 | This species were plunged into decades of civil war after a Starfleet officer gave them advanced weapons.329 | Too Short a Season |
| Mordian Butterfly206 | Insectoid life form which resides on Mizar II206 | Profit and Loss |
| Morg / Eymorg330 | The females and males of the same species who reside on Sigma Draconis VI.330 | Spock's Brain |
| Moropa95 | Society hostile to the Bolians95 | Allegiance |
| Mugato236 | White simian creature with a highly poisonous bite236 | A Private Little War |
| Muktok Plant12 | Plant native to Betazed.12 | Menage a Troi |
| Muse331 | This non-corporeal species takes corporeal form and feeds off the creative energy of artists.331 | The Muse |
| Mylean332 | Delta Quadrant civilisation similar to Talaxians332 | Scientific Method |
| N'Kree275 | This Delta Quadrant species attempted to conscript a duplicate of Voyager into their battle fleet nine months and two days prior to Stardate 52586.3275 | Course: Oblivion |
| Na'kuhl53 | A faction of the Temporal Cold War which assisted the Nazis in an alternate timeline version of World War II.53 | Storm Front, Part I |
| Nacene266 | A highly advanced species, a member of the Nacene known as the Caretaker was responsible for dragging various spacecraft into the Delta Quadrant.266 A millennia ago the Nacene accidentally caused an environmental disaster on the Ocampa home planet; two of their kind remained to provide for the surviving Ocampa who they housed in an underground city. Eventually one of these Caretakers left333, while the other died in 2371.334 | Caretaker, Part 1 |
| Nagilum335 | Noncorporeal lifeform which experimented on the Enterprise D crew to determine the nature of death335 | Where Silence Has Lease |
| Nakan336 | People who were massacred several centuries ago.336 | Memorial |
| Nanites337 | Artificial life form created by Wesley Crusher337 | Evolution |
| Napean338 | Humanoid species. Napeans are empathic, and are capable of cross-breeding with Humans.338 | Eye of the Beholder |
| Nasari339 | The Nasari are sworn enemies of the Taresians, and will attack any ship carrying a Taresian on sight.339 | Favorite Son |
| Nassordin59 | Delta Quadrant civilisation which traded with the B'omar59 | The Raven |
| Nasturtium109 | Terran plant109 | Imaginary Friend |
| Nausicaans340 | Large Humanoids noted for their aggressiveness and lack of subtlety340 | Samaritan Snare |
| Nechani341 | Species who were willing to allow Kes to die for unwittingly breaking one of their religious laws.341 | Sacred Ground |
| Neethian Catfish181 | Creature which can survive being cut in half.181 | Vox Sola |
| Neo-Roman342 | Humanoid species from a planet which paralleled earth's early development but on which the Roman empire never fell.342 | Bread and Circuses |
| Neuralian236 | Species who lived in peace until the Klingons and Federation armed them, starting a civil war.236 | A Private Little War |
| Nexian tapeworm343 | Parasitic worm which can live within Denobulans. It attaches itself to the lower intestinal tract and absorbs nutrients from there; as a side effect, the host will tend to lose weight. Phlox used one of the creatures for this purpose in 2154343 | The Council |
| Nezu197 | Voyager helped the Nezu resist an asteroid bombardment in 2373.197 | Rise |
| Night Beings307 | Delta Quadrant civilisation who lived within the Void and were well adapted to the conditions there307 | Night |
| Nihydron19 | Delta Quadrant civilisation; in an alternate timeline the Nihydron allied with Voyager against the Krenim19 | Year of Hell, Part 1 |
| Nitrium Metal Parasites283 | Spaceborne lifeform which eats metals and converts it into a viscous liquid283 | Cost of Living |
| Noophians143 | Species which have no sentimental attachment to old things.143 | Brothers |
| Norcadians344 | Humanoid Delta Quadrant species.344 Borg designation Species 686276 | Tsunkatse |
| Norpin Falcon345 | Bird from the planet Norpin known for its excellent reflexes345 | Sons and Daughters |
| Nucleogenic Cloud Being152 | Life form measuring over a billion kilometres in diameter152 | The Cloud |
| Nucleogenic Lifeform35 | A species which was considered to be spiritually important by the Ankari. The bodies of these creatures yielded a substance which greatly improved the effectiveness of warp drive, and the crew of the Equinox killed many of them to assist them in their journey home.35 The Equinox was eventually destroyed in retaliation.36 | Equinox, Part 1 |
| Numiri70 | Enemies of the Banea, the Numiri are notoriously hostile to outsiders.70 | Ex Post Facto |
| Nuu'bari346 | Species which used simple holograms for mining duties.346 | Flesh and Blood, Part 1 |
| Nuvian53 | Species to be found on various planets around Earth. Nuvian masseuses were highly prized, having twelve fingers on each hand. Risa had over 200 of them in 2152.315 Nuvian concubines were to be found for sale in slave markets in the Delphic Expanse.347 | Fallen Hero |
| Nyberrite Alliance348 | Spacefaring civilisation348 | The Way of the Warrior |
| Nygean82 | Species which uses the death penalty on criminals.82 | Repentance |
| Nyrian48 | Species which captures ships by gradually swapping the crew for their own people via a long range transporter. The Nyrians are sensitive to high levels of light and humidity, and to low temperatures.48 | Displaced |
| Ocampa266 | Civilisation native to the Delta Quadrant who have an average lifespan of nine years266 | Caretaker, Part 1 |
| Old Ones349 | Civilisation which used to inhabit Exo III but are now extinct, leaving only their androids behind349 | What Are Little Girls Made Of? |
| Old Ones350 | Leaders of a species which attempted to invade the Federation350 | Catspaw |
| Onaya331 | Noncorporeal species which thrive on the energy of creativity331 | The Muse |
| Ophidian164 | Serpentine creature capable of opening rifts in time164 | Time's Arrow, Part 1 |
| Oran'takuans | Natives of the planet Oran'taku, a class M world in the Delphic Expanse about half a light year from the Xanthan home planet. A member of this species, Rajiin, infiltrated the NX-01 for the Xindi in 2153351 | Rajiin |
| Organians274 | Noncorporeal species of great power who are horrified by violence274 | Errand of Mercy |
| Orillian Lung Maggot102 | Form of life native to the Orillian home world102 | Fair Trade |
| Orion Wing-slug12 | Animal life form12 | Menage a Troi |
| Ornarans104 | The entire Ornaran species was composed of addicts of the drug Felicium.104 | Symbiosis |
| Orsic fern211 | Plant which Dr. Phlox kept in his sickbay.211 | Similitude |
| Osaarian10 | Species which the NX-01 Enterprise encountered in the Delphic Expanse, though they were not native to there. The Vulcan high command had not had a great deal of contact with them as of 2153, but did know that they had a large merchant fleet. The associated image shows an Osaarian with severe facial disfigurations.10 | Anomaly |
| Osmotic Eel20 | Creature used by Dr. Phlox to treat wounds.20 | Broken Bow |
| Oysters352 | Terran sea creature considered an aphrodisiac by some352 | His Way |
| Pah-wraiths125 | Noncorporeal beings apparently originating on Bajor; opponents of the Prophets125 | The Assignment |
| Pakleds340 | Humanoid civilisation not known for the intellect340 | Samaritan Snare |
| Palmarian30 | As of 2373 the Palmarians were engaged in a brutal civil in which both sides sought to use biogenic weapons.30 | Business as Usual |
| Palukoo353 | Large spider-like animal life form native to many of the Bajoran moons. The Bajoran terrorists used to eat them.353 | The Siege |
| Paraagan354 | Matriarchal society as of 2152, though the males had made great strides in acquiring equal rights by this date. A Paraagan mining colony was destroyed with the loss of 3,600 lives in 2152, apparently by an accident caused by one of Enterprise's shuttlepods. In fact the Suliban were responsible for the accident.354 | Shockwave, Part 1 |
| Parada355 | Slightly reptilian humanoid species native to the Gamma Quadrant.355 | Whispers |
| Parein202 | Humanoid civilisation composed of former Borg drones202 | Unity |
| Paxans168 | Highly isolationist species who refuse to allow any knowledge of themselves to be known by outsiders. The Paxans are capable of occupying the bodies of others, as shown in the associated image.168 | Clues |
| Peliar-zelians | This species inhabited the planet Peliar-Zel, as well as its two moons Alpha and Beta. In 2337 the Trill Ambassador Odan mediated a dispute between the two moons. In 2367 Odan returned, this time in a new host, and mediated another conflict which had arisen because Alpha moon was developed an energy source which drew power from the planet's magnetic field, causing substantial environmental damage to Beta moon.356 Members of this species are a common sight in the Federation and Federation-related areas. In 2369 one attended a Starfleet hearing into the death of a cadet357; they were a common sight on Deep Space Nine118, and on one occasion assisted in the kidnapping of William Patrick Samuels for the Cardassians.73 Members of this species were also present at Worf and Dax's wedding65, and when Odo professed his love for Kira on the Promenade.352 One was also a customer in Joseph Sisko's restaurant on Earth in 2372222 | The Host |
| Peljenite358 | Species invited to join the Federation in 2371358 | Family Business |
| Pendari344 | Reknowned for their physical strength, a Pendari fought in the Tsunkatse matches shown on the Norcadian home world.344 | Tsunkatse |
| Pentarans209 | A Pentaran once crashed his shuttle whilst Captain Picard and Ensign Crusher were on board.209 | Final Mission |
| Petarian358 | Spacefaring civilisation358 | Family Business |
| Photonic being359 | Noncorporeal being found to reside in a protostar. Other types of photonic being live in a parallel dimension.359 | Heroes and Demons |
| Photonic Flea262 | Tuny glowing insect which once invaded Voyagers sensor system and caused false readings262 | The Voyager Conspiracy |
| Photonic Lifeform360 | Encountered by Voyager while stranded on a subspace sandbar.360 | Bride of Chaotica! |
| Pipius208 | Presumed name of an animal life form. Pipius claw is a Klingon foodstuff.208 | A Matter of Honor |
| Platonian361 | More formally known as 'The Children of Plato', the Platonian's had extremely strong telekinesis.361 | Plato's Stepchildren |
| Polonians362 | Delta quadrant species, enemies of Mr Varn362 | Live Fast and Prosper |
| Ponea35 | Delta Quadrant species. The Ponea were encountered by the Equinox crew, and gave Captain Ransom a synaptic stimulator device which allowed him to experience virtual reality landscapes.36 | Equinox, Part 2 |
| Pralor144 | Extinct delat quadrant species which created a race of robots to fight the Cravic144 | Prototype |
| Preservers363 | Ancient civilisation who transplanted members of primitive peoples to distant planets363 | The Paradise Syndrome |
| Progenitors5 | Ancient civilisation who seeded genetic codes on many worlds5 | The Chase |
| Promellian319 | Now extinct, the Promellians fought a devastating war about a thousand years ago.319 | Booby Trap |
| Prophets127 | Noncorporeal alien species which have transcended linear time. The Prophets created and maintain the Bajoran Wormhole and are religious figures to the Bajorans.127 | Emissary |
| Proto-Vulcans325 | These primitives suffered cultural contamination from an accidental first contact with the Federation.325 | Who Watches The Watchers? |
| Providers364 | The poviders lived as organic brains inside a life support machine.364 | The Gamesters of Triskelion |
| Proxcinians30 | Civilisation at war as of 237330 | Business as Usual |
| Prytt271 | Humanoids native to the planet Kesprytt II271 | Attached |
| Psi 2000 Virus365 | Water-based virus which behaves in the body like alcohol365 | The Naked Time |
| Pycan space moth175 | Animal life form. Dr. Phlox heard of a moth which drifted half a light year whilst trying to return to its homeworld.175 | Doctor's Orders |
| Pygmy Marmoset27 | Small Earth primate that Data thought Picard might de-evolve into27 | Genesis |
| Pygorians366 | Interstellar traders. Quark put Sakonna in touch with Pygorians who sold her weapon systems.366 | The Maquis, Part 2 |
| Pyrithian bat28 | Creature which Dr. Phlox used in his sickbay. His bat was a picky eater, and would not eat anything once it was dead.28 | Fight or Flight |
| Pyrithian Moon Hawks24 | Predatory animal which feeds on Pyrithian bats.24 | A Night In Sickbay |
| Q69 | Proper and species name for any of a group of nearly omnipotent transdimensional beings69 | Encounter at Farpoint |
| Qomar367 | Advanced Delta Quadrant species who had no concept of music prior to encountering Voyager.367 | Virtuoso |
| Quantum Singularity Life Form368 | Sentient species which incubates its young in a black hole368 | Timescape |
| Quarren369 | An advanced and highly industrialised species in the Delta Quadrant, the Quarren planet was undergoing a crippling labour shortage in the 2370s. To overcome this, they took to abducting the crews of passing starships, using false memory implants to convince the crews that they had willingly chosen to work on the planet. As a result, the Quarren home planet is highly cosmopolitan, with workers from many different species present. The bulk of Voyager's crew were so captured in 2377369, but the few remaining crew were able to rescue them.370 | Workforce, Part 1 |
| Quasi-energy Microbes302 | Life forms found within a plasma streamer302 | Realm of Fear |
| Rabbit371 | Small furry terran animal. A large, fully clothed, bipeddel, white rabbit was onced seen by Dr McCoy on the amusment park planet. Data once saw a shape of a rabbit in a nebula gas formation.371 | Shore Leave |
| Racht190 | Klingon worm-like animal, eaten live - very similar to gagh in appearence and may be related.190 | Melora |
| Rafalian Mouse372 | Small rodent which Odo enjoyed mimicking372 | Crossfire |
| Rakharan21 | The Rakharan government punished families of political disidents21 | Vortex |
| Rakonian Swamp Rat373 | Unpleasant animal. Kira thought Quark had some similarities to this creature373 | Hippocratic Oath |
| Rakosan374 | The Rakosans were threatened with devastation by the Cardassian Dreadnought, but were saved by the USS Voyager.374 | Dreadnought |
| Ram Izad19 | Species erased from history by Annorax in an attempt to restore the Krenim Empire to existence.19 | Year of Hell, Part 1 |
| Ramuran375 | Ramurans are heavily isolationist, and use a combination of technology and biology to ensure that nobody remembers encountering them.375 | Unforgettable |
| Rat261 | Rodent species native to Earth, considered a pest by most Humans.261 | Oasis |
| Razor Toothed Gree Worms376 | Small animal known for it's sharp teeth.376 | Little Green Men |
| Rectillian Vulture377 | Avian life form native to the Delta Quadrant377 | Phage |
| Rectyne Monopod378 | Creature which can weigh up to two tons378 | The Icarus Factor |
| Redjac49 | Noncorporeal being who feeds on negative emotions, which it provokes by savage murder49 | Wolf in the Fold |
| Reegrunion379 | Alien species. The wanted criminal Plix Tixiplik was a Reegrunion.379 | Sanctuary |
| Reeta-hawk51 | Avian life form from the planet Argratha51 | Hard Time |
| Regalian Fleaspider380 | Arachnid which can be used to create medicine to improve circulation380 | The Ship |
| Regulan Blood Worm160 | Soft shapeless creature which some Klingons think similar in appearance to Kirk160 Captain Archer once used Regulan bloodworms as part of a deception he played on the Xindi Degra.308 | The Trouble With Tribbles |
| Remans282 | Species which are slaves of the Romulans.282 | Star Trek : Nemesis |
| Retellians381 | Species encountered by the NX-01 Enterprise in 2152.381 | Precious Cargo |
| Rhaandarite91 | Members of the United Federation of Planets, the Rhaandarites are a humanoid species native to the planet Rhaandaran. They are very long lived, and do not reach maturity until they reach a century and a half or so.92 | Star Trek : The Motion Picture |
| Rigel VII Warrior239 | A warrior from Rigel VII; when the Enterprise visited the planet in 2254, one of these warriors killed three memebers of the crew and injured seven others. Captain Pike was forced to relive an altered version of the scene by the Talosians when they captured him shortly afterwards.239 | The Cage |
| Rigelians32 | Species similar to Vulcans.32 | Journey to Babel |
| Rigellian158 | There are two breeds of Rigellians; one is descended from saber-toothed turtles.44 Phlox stated that Rigellians have four or five genders.382 | Star Trek : The Motion Picture |
| Rigellian ox383 | Creature known for being very healthy.383 | The Schizoid Man |
| Rilnar19 | The first species erased form history by Annorax. The erasure caused a near-total restoration of the Krenim Empire, but caused a rare disease amongst their colonies which killed fifty million people. Annorax realised that the Rilnar had introduced a crucial antibody into the Krenim genome, so erasing them had directly led to the deaths.19 | Year of Hell, Part 1 |
| Risan sea turtle384 | Aquatic animal native to Risa.384 | Two Days and Two Nights |
| Risans150 | Hedonistic humanoid species native to the Alpha quadrant.150 | Captain's Holiday |
| Romulans385 | Major species with a long history of hostility toward the Federation and Klingons385 | Balance of Terror |
| Ruji210 | Sisko and Curzon once encountered a pair of seven foot tall Ruji twin sisters whilst attending the running of the Rujian Steeplechase.210 | A Man Alone |
| Rukani386 | Delta Quadrant civilisation who featured in a holodeck training program created by Tuvok386 | Worst Case Scenario |
| Rutian387 | The Rutians suffered years of conflict at the hands of the evil Ansata terrorists.387 | The High Ground |
| Sakari388 | Species which was devastated by the Borg and subsequently attempted to hide their existence to avoid further attacks.388 | Blood Fever |
| Saltah'na389 | Gamma Quadrant species; they produced telepathic objects which could affect the minds of others389 | Dramatis Personae |
| Samarian Coral Fish109 | Aquatic lifeform which are sometimes perceived in nebula clouds109 | Imaginary Friend |
| Sand Bats390 | Creatures which appear to be inanimate rock crystals, until they attack390 | The Empath |
| Sark, Klingon179 | Riding animal179 | Pen Pals |
| Sarpeidonian391 | When their planet was threatened by a nova, this species saved themselves by traveling into their past.391 | All Our Yesterdays |
| Sarthonian150 | Natives of Sarthong V. The Sarthonians strongly opposed any trespassers on their planet150, though this did not stop Vash from going there.13 | Captain's Holiday |
| Satarran183 | The Satarrans were unable to win their war with the Lysians, and so used mind control techniques to make the Enterprise-D crew attack them instead.183 | Conundrum |
| Saurian158 | Saurians were members of the Enterprise crew during the V'Ger incident of 2371.158 | Star Trek : The Motion Picture |
| Scalosians392 | Species which were hyper-accelerated due to environmental damage to their planet.392 | Wink of an Eye |
| Scathos223 | Species who kill any woman under forty who conceives a child223 | Elogium |
| Screetch rhino229 | Creature which could weigh 3,000 tons. Dax promised Sisko that a holographic image projector could make him look like a Screetch rhino.229 | Second Skin |
| Sehlat32 | Vulcan animal resembling a Teddy Bear, but with six inch fangs32 | Journey to Babel |
| Selay40 | Deadly enemies of the Anticans, the Selay were also considered for Federation membership in 2364.40 | Lonely Among Us |
| Seltan Carnosaur393 | Reptilian lifeform approximately 300 metres tall393 | One Little Ship |
| Serosians57 | Delta Quadrant species from the planet Seros; the Serosians used isomorphic projections as menial labourers. In 2374 Voyager's crew encountered a projection which had murdered the crew of his ship.57 | Revulsion |
| Sheliak224 | Mysterious and powerful species who signed a complex treaty with the Federation224 | The Ensigns of Command |
| Shib'a lizard394 | Type of animal native to an alien planet. They don't move very fast.394 | Marauders |
| Shivolians273 | Delta Quadrant species, Borg designation Species 521273 | Survival Instinct |
| Sikarians395 | Species which are able to transport instantly up to 40,000 light years from their home world395 | Prime Factors |
| Sinoraptor396 | Life form396 | The Darkness and the Light |
| Skagarans93 | Intelligent species native to the Delphic Expanse. The Skagarans abducted groups of Humans from Earth in circa. 1864 for use as slave labour on a colony world in the Expanse. The Humans rebelled against their masters and overthrew them; unfortunately the Humans then established a legal system in which Skagarans had very few rights and were themselves poorly treated. The Humans and Skagarans began to move towards mutual tolerance in 2154 thanks to the intervention of the NX-01 Enterprise.93 | North Star |
| Skreean379 | A gamma Quadrant species. Fleeing the Dominion, the refugee Skreean mistook Bajor for their promised land in 2370, but were not allowed to settle there by the government.379 | Sanctuary |
| Sky Spirits147 | Human name for a delta quadrant species which visited Earth tens of thousands of years ago.147 | Tattoo |
| Sloth28 | Earth animal to be found near the Amazon river as of 2151.28 | Fight or Flight |
| Sluggo28 | Slug-like creature, one of the first lifeforms discovered by the NX-01 on its exploration mission.28 | Fight or Flight |
| Snow beetles397 | Creature which Dr. Phlox kept in sickbay to feed to his other animals.397 | Chosen Realm |
| Solais295 | The Solais warred for centuries, but were helped towardspeace by the mediator Riva.295 | Loud as a Whisper |
| Solanagen based life forms131 | Existing in a parallel dimension, these beings abducted several members of the Enterprise-D crew to experiment on them.131 | Schisms |
| Son'a62 | Spacefaring civilisation; an offshoot of the Ba'ku62 | Star Trek : Insurrection |
| Soong-type Android145 | Form of Android based around a positronic network145 | Datalore |
| Soukara Lizard398 | Creature found on the planet Soukara. Worf and Jadzia encoutered one of these whilst on a covert mission to the planet.398 | In the Pale Moonlight |
| Soukaran Snake398 | Reptilian life form from the planet Soukara. Worf and Jadzia saw one of these whilst on a covert mission to the planet.398 | In the Pale Moonlight |
| Space Shrimp223 | Space going life form which Voyager encountered in 2371.223 | Elogium |
| Space Whales399 | Lifeform which lived entirely in space. One newborn of this species thought the Enterprise D was its mother399 | Galaxy's Child |
| Spawn Beetle223 | Insect223 | Elogium |
| Species 10026287 | Delta quadrant species assimilated by the Borg in 2375.287 | Dark Frontier, Part 1 |
| Species 116400 | A member of this species attempted to have the crew of Voyager assimilated by the Borg.400 | Hope and Fear |
| Species 125287 | Species of which the Borg Queen is a member287 | Dark Frontier, Part 1 |
| Species 149267 | Species assimilated by the Borg; the assimilation gave the Borg advanced medical technology267 | Mortal Coil |
| Species 259401 | Borg designation for a species which resided in Galactic cluster 3401 | The Gift |
| Species 262402 | A primitive species assimilated by the Borg around 2145; the Borg gained some knowledge of the Omega molecule from this species402 | The Omega Directive |
| Species 263402 | Species assimilated by the Borg; the species believed the Omega molecule was a drop of their creators blood402 | The Omega Directive |
| Species 312292 | Species assimilated by the Borg; this species used a type of shield technology which Voyager encountered protecting a primitive species on a planet in the Delta Quadrant.292 | Natural Law |
| Species 5174237 | Borg designation for a Delta Quadrant civilisation237 | Hunters |
| Species 571273 | Delta quadrant humanoids who worship Brothera.273 | Survival Instinct |
| Species 5973403 | A species encountered by the Borg in galactic cluster eight. Species 5973 are multi-spectrum particle life-forms.403 | The Haunting of Deck Twelve |
| Species 6339404 | A species largely assimilated by the Borg which attempted to fight back by infecting the collective with a virus.404 | Infinite Regress |
| Species 8472405 | Immensely powerful species from Fluidic space who are virtually immune to conventional technologies.405 | Scorpion, Part 1 |
| Spores, Omicron Ceti III87 | Symbiotic organism which protect their host from Berthold rays87 | This Side of Paradise |
| Squid297 | Terran water dweller297 | Blaze of Glory |
| Squill304 | Plant from the planet Balancar304 | The Magnificent Ferengi |
| Srivani406 | Voyager encountered this species in 2374. The Srivani are an advanced race posessing sophisticated cloaking technology resembling the phase cloak developed by renegade Federation officers. They use this technology to infiltrate alien vessels and conduct medical experiments on the crew without their knowledge. The Srivani hold that such experiments are justified as the development of new medical treatments saves more lives than are taken in the experiments. Seven of Nine was able to detect the presence of the Srivani, and Captain Janeway forced them to withdraw by piloting Voyager near-suicidal course between a pair of pulsars. As the Srivani ships docked to Voyager's hull withdrew at least one of them was destroyed.332 | Scientific Method |
| Stromatopod larvae61 | The ECS Horizon was delivering a cargo of these creatures to the Demerians in 2153.61 | Horizon |
| Subytt407 | Species. A Subytt first officer was attempting to smuggle defective isolinear rods to Bajor in 2370. He was caught after a tip-off from Quark.407 | The Homecoming |
| Suliban20 | Humanoid species from Sector 3641. Although most are non hostile, certain Suliban have genetically engineered themselves and are engaged in a temporal cold war.20 | Broken Bow |
| Sun vipers93 | Animal life form native to the Skagaran planet discovered in the Delphic Expanse by the NX-01 Enterprise93 | North Star |
| Swarm326 | Mysterious species who attack all those who enter their space.326 | The Swarm |
| T'gla272 | Mindless life form, probably native to a Klingon world, which lets itself be slaughtered. Probably non-sentient.272 | Invasive Procedures |
| T'Kon204 | Last living subject of the T'Kon Empire204 | The Last Outpost |
| T'Lani268 | Once enemies of the Kellerun, the T'Lani created deadly Harvester weapons and then tried to destroy all knowledge of them once the war ended.268 | Armageddon Game |
| T'stayan408 | Talarian riding animal408 | Suddenly Human |
| T-Rogorans379 | Gamma Quadrant species. The T-Rogorans were enemies of the Skreeans for eight centuries, conquering them and using them as forced labourers. The Skreeans were freed and scattered when the T-Rogorans were in turn conquered by the Dominion.379 | Sanctuary |
| Tagrans409 | Natives of Tagra IV.409 | True-Q |
| Taguan110 | Culture whose pottery resembles both Marlonian and Buranian work.110 | Rascals |
| Taguans13 | Natives of Tagua III. Little known of the origins of the Taguans and they no longer allow archeological research on their planet. Q claimed that the Taguans really knew how to party two billion years ago.13 | Qpid |
| Tairenian Ant108 | A type of ant. Mezoti made a Tairenian Ant colony for her science project in 2376. The drones produce a flourescent enzyme which is activated by the queen, causing them to glow.108 | Child's Play |
| Tak Tak213 | Gestures make up a large part of the Tak Tak language, and they can become very offended by unsuitable body language.213 | Macrocosm |
| Takaran410 | Takarans are immensely difficult to kill as a result of their unique cell structure.410 | Suspicions |
| Takarian411 | The Tkarians suffered under the illusion that a pair of Ferengi were mystical sages for a number of years.411 | False Profits |
| Takret184 | Likely name for the species which attempted to steal the NX-01 Enterprise in 2152. The species was not named specifically, but they came from the Takret system and the force which boarded Enterprise was called the Takret Militia.184 | The Catwalk |
| Talarian408 | The Talarians once fought a war in which they kidnapped a Human child and raised him as one of their own species. 408 | Suddenly Human |
| Talarian Hook Spider302 | Arachnid with legs half a metre long302 | Realm of Fear |
| Talavians412 | Civilisation412 | Things Past |
| Talaxians266 | Delta Quadrant civilisation266; Borg designation Species 218.59 | Caretaker, Part 1 |
| Talosians239 | Humanoids with powerful telepathic abilities239 | The Cage |
| Tamarians187 | Humanoid species which communicates entirely by metaphor187 | Darmok |
| Tandarans413 | The Tandarans were enemies of the Suliban, and interned the Suliban people who lived within their territory.413 | Detained |
| Tanugans414 | The Tanugans have a legal system in which one must prove one's innocence.414 | A Matter of Perspective |
| Tarchee Cat341 | Species indigenous to Nechani home world341 | Sacred Ground |
| Tarellians6 | The Tarellian species virtually wiped itself out with biological warfare. The few survivors wandered as outcasts for many years.6 | Haven |
| Taresian339 | Taresians reproduce by abducting males from other species and denucleating their cells.339 | Favorite Son |
| Targ415 | Klingon animal sometimes kept as a pet415 | Where No One Has Gone Before |
| Targhee Moonbeast170 | Life form noted for its loud call170 | The Perfect Mate |
| Tarkalean416 | Species which posessed replicator technology as of 2152.416 A Tarkalean ship was attacked by Borg drones in 2153.417 The Tarkaleans are known for their tea.257 In 2372 one of the many additional charges the Ferengi imposed on their business dealings with the Karemma was claimed to be to cover the lost income of Tarkalean sheep herders.418 | Dead Stop |
| Tarkalean Condor312 | Large bird312 | ...Nor the Battle to the Strong |
| Tarkalean Field Mouse344 | Animal known for its small size344 | Tsunkatse |
| Tarkalean Hawk23 | Predatory bird23 | The Begotten |
| Tarkannans176 | Civilisation176 | Innocence |
| Tarkassian Razorbeast109 | Animal. Guinan had a Tarkassian Razorbeast as an imaginary friend109 | Imaginary Friend |
| Tarlac62 | Species which was conquered by the So'na and converted into a working class.62 | Star Trek : Insurrection |
| Taureans419 | These large ape-like creatures are inhabitants of Taurus II. They are primitive creatures, 12 feet or more in height and possessed of great strength but with only the most rudimentary technology - spears made of stone and wood, shields of leather. Their culture was believed to comprise family groups or tribes. They were highly aggressive, prone to attacking intruders and responding to any attack upon themselves with considerable anger.419 | The Galileo Seven |
| Tavnian331 | In Tavnian weddings the husband must convince every person present that he is truly in love with his fiancee before he can marry her. Tavnian men own their male offspring.331 | The Muse |
| Telsian362 | Delta Quadrant species which ran a mining facility on Telsius Prime. A group of confidence tricksters stole ten kilotons of bolomite ore from them whilst masquerading as Voyager crewmembers.362 A Telsian miner was duped by Gar as part of his network of cons in 2377.167 | Live Fast and Prosper |
| Temporal parasites420 | Creatures from a domain outside normal space-time, which exist in a state of interspatial flux. They could infect a Human host, causing an inability to form long term memories. When one was killed, it vanished from the host's brain as if it had never existed in the first place.420 | Twilight |
| Tenebian skunk421 | Animal possibly kept as a pet aboard the Human cargo vessel Fortunate.421 | Fortunate Son |
| Terellians254 | Four limbed species254 | Liaisons |
| Terkellians262 | Civilisation with whom Voyager signed a non agression pact.262 | The Voyager Conspiracy |
| Terrelian seapod36 | Life form which Chakotay once learned to speak with. He believed that communicating with nucleogenic life forms could be no harder.36 | Equinox, Part 2 |
| Terrellians422 | Civilisations422 | Life Support |
| Tesnians423 | Species encountered by the NX-01 Enterprise. Tesnians can breathe an Earth-standard atmosphere, but only if it is supplemented by boron gas for at least six hours each day.423 | Shuttlepod One |
| Thasians246 | Species that rased Chalie X and gave him PSI powers.246 | Charlie X |
| Tholians424 | Sentient creatures who are less than friendly to outsiders424 | The Tholian Web |
| Tiberian Bats133 | Avian life form known for staying together.133 | Star Trek VI : The Undiscovered Country |
| Tiburonians406 | Federation members. Dr Sevrin belonged to this species.425 One of the officers killed during Captain Sisko's attempt to sieze a crashed Dominion attack ship was a Tiburonian.426 | The Way to Eden |
| Tiger371 | Large Terran feline371 | Shore Leave |
| Tika Cat427 | Small animal not known for its bravery427 | Faces |
| Tilonian428 | The Tilonians once kidnapped Commander Riker and attempted to coerce information out of him.428 | Frame of Mind |
| Torga429 | Animal native to the planet Gaia429 | Children of Time |
| Tosk241 | Species bred to act as prey for the Hunters241 | Captive Pursuit |
| Trabe430 | Former masters of the Kazon, now reduced to nomadic wanderings after being overthrown.430 | Alliances |
| Traveller415 | Natives of Tau Alpha C who manipulate time and space with their thoughts.415 | Where No One Has Gone Before |
| Trayken Beast237 | Large and powerful alien life form237 | Hunters |
| Trelane431 | Member of a powerful species similar to the Q431 | The Squire of Gothos |
| Trellan Crocodile372 | Large animal known for its strength and destructiveness372 | Crossfire |
| Triannons397 | Inhabitants of the planet Triannon in the Delphic Expanse. The Triannons were religious fanatics.397 | Chosen Realm |
| Tribbles160 | Small furry creatures famed for their prodigious reproduction160 | The Trouble With Tribbles |
| Trill356 | Species composed of a Humanoid Host and a Symbiont356 | The Host |
| Trill Host356 | Humanoid civilisation who are capable of carrying Trill Symbionts356 | The Host |
| Trill Symbiont432 | Small sluglike creature which is capable of joining its personality with a Humanoid host432 | Equilibrium |
| Troglytes47 | One of the groups living on Ardana47 | The Cloud Minders |
| Troyian189 | The Troyians were deadly enemies of the Elasians until a peace treaty in 2268.189 | Elaan of Troyius |
| Tsetse Fly433 | Insect433 | Ship in a Bottle |
| Tube Grubs434 | Ferengi animal434 | The Jem'Hadar |
| Turei435 | One of the species which almost destroyed the Vaadwaur 900 years ago, and which now control part of their underspace corridor network.435 | Dragon's Teeth |
| Two-Dimensional Creatures436 | Species encountered by the Enterprise-D436 | The Loss |
| Two-Headed Malgorian14 | Life form famed for its indecision14 | Progress |
| Two-tailed Talchok225 | Animal native to the planet Rinax. Talchoks have sharp claws and dripping fangs and are considered to be vermin by the Talaxians. When he was a child Neelix devised a fool-proof Talchok trap. When he found one of the creatures pinned in the trap squealing and squirming in agony, he realised that in fact it was just an innocent animal like any other.225 Since Neelix specified the number of tails, it is possible that there are other variants of the Talchok with different numbers of tails. | Jetrel |
| Tygarian407 | A humanoid species often seen around the Federation. In 2370 Li Nalas tried to sneak off Deep Space Nine by disguising himself as a crewmember on a Tygarian freighter.407 A Tygarian was present in the bar on Dessica II when the Enterprise-D senir officers searched it for evidence of Captain Picard.155 Tygarians were also a frequent sight on Deep Space Nine.118 At least some Tygarians are fond of tribbles.437 | The Homecoming |
| Tyran199 | The Tyrans developed a revolutionary mining technology which the Federation considered using in 2369.199 | The Quality of Life |
| Tzenkethi438 | Alpha Quadrant Species438 | The Adversary |
| U'tani347 | Species to be found in the Delphic Expanse. U'tani serpent women were sold at a slave market in the area.347 | Rajiin |
| Ullian135 | An Ullian once used his telepathic power to forcibly extract memories from the crew of the Enterprise-D. 135 | Violations |
| Ux-Mal439 | The Ux-Mal confined the disembodied 'souls' of their criminals to the Mab-bu IV, where some of them took over the bodies of Enterprise-D crew members.439 | Power Play |
| V'Ger158 | Powerful machine lifeform based on the NASA probe Voyager 6158 | Star Trek : The Motion Picture |
| V'radian347 | A V'radian scientist gave the NX-01 Enterprise crew a method of creating Trellium D in 2153.347 | Rajiin |
| Vaadwaur435 | Delta quadrant species which were a major power circa 1370. The Vaadwaur were considered ruthless and agressive by many who encountered them; they used a network of Underspace corridors to attack many other species. The Vaadwaur were eventually defeated by an alliance of other species and the surface of their homeworld largely destroyed. In 2376 Voyager found a large group of Vaadwaur in stasis and released them. They fled into the corridor network, apparently planning on resuming their aggressive ways.435 | Dragon's Teeth |
| Vaalians440 | Subjects of the computer god Vaal, these people lived for thousands of years.440 | The Apple |
| Vakol Fish441 | Delta Quadrant life form441 | State of Flux |
| Valakians305 | This primitive Humanoid species were not capable of warp flight as of 2151, and sought the help of more advanced races to cure a plague which was threatening them.305 | Dear Doctor |
| Valerian389 | Spacefaring species. The Valerians were thought to have traded weapons grade Dolamide to the Cardassians during the Bajoran occupation.389 | Dramatis Personae |
| Valtese170 | Species native to the Vault Minor system170 | The Perfect Mate |
| Vanoben21 | A pair of twinned Miradorn were suspected of stealing an artefact from a Vanoben transport two light years from Deep Space Nine in 2369.21 | Vortex |
| Varro442 | Species which wandered the stars for centuries in a multi-generational ship.442 | The Disease |
| Vaskan288 | Species which was attacked by the Kyrians whilst Voyager was in the area. Voyager would be blamed for the war by the Kyrians centuries later.288 | Living Witness |
| Vek30 | Civilisation. During his time as an arms dealer Quark falsely informed Hagath that he couldn't supply him with a mutagenic retrovirus because he had sold it all to the Minnobia for use in their war against the Vek.30 | Business as Usual |
| Vencidian344 | Delta Quadrant species.344 | Tsunkatse |
| Vendikarans192 | Species who fought a war with the neighbouring planet Eminiar entirely by computer.192 | A Taste of Armageddon |
| Ventaxian443 | Species which believed that their version of the devil had come to claim posession of their planet.443 | Devil's Due |
| Ventu292 | Primitive Delta Quadrant species which lived on the Ledosian homeworld. The Ventu were unable to gain the benefits of Ledosian technology because they were imprisoned behind a force field which had been set up on the planet in the distant past, possibly by Species 312.292 | Natural Law |
| Verillians30 | Species which bought weapons off Quark30 | Business as Usual |
| Vhnori212 | The Vhnori send their dead to a planetary ring in the Delta Quadrant via naturally occurring subspace vacuoles.212 | Emanations |
| Vians390 | Mysterious species which tested others to determine their worth.390 | The Empath |
| Vicarian Razorback444 | Animal noted for its viciousness444 | The Die is Cast |
| Vidiians377 | Species inflicted with the Phage377 | Phage |
| Vissians382 | Species which the NX-01 Enterprise encountered in 2153. The Vissians have three genders - male, female and a cogenitor gender. The cogenitors were not considered to be equals of the males and females as of 2153.382 | Cogenitor |
| Void Aliens445 | Delta Quadrant species which lived within a subspace void which trapped ships that approached it. The Void aliens were highly intelligent, but were unable to talk. They had a natural stealth ability which allowed them to stow away on the ships within the void.445 | The Void |
| Vok'sha359 | Civilisation from Rakella Prime359 | Heroes and Demons |
| Vorgon150 | In the future, two criminals of this species will use time travel in an attempt to locate the Tox'utat.150 | Captain's Holiday |
| Vori284 | Species which used brain washing techniques to convince aliens to fight for them in their war with the Kradin.284 | Nemesis |
| Vorian Pterodactyl446 | Large flying animal. When Odo and Quark had to carry a subspace transmitter up a mountain, Odo commented that a Vorian Pterodactyl could have carried it up there easily.446 | The Ascent |
| Vorta434 | Species enhanced by the Dominion to become political representatives434 | The Jem'Hadar |
| Vostigye447 | Delta Quadrant species who contacted Voyager in 2373. Unfortunately, the station which hailed Voyager was destroyed by a natural phenomenon shortly afterwards.447 | Real Life |
| Voth196 | Humanoid ife form descended from Terran dinosaurs196 | Distant Origin |
| Vulcan Mollusks190 | Animal life form native to Vulcan. Large mollusks were considered a delicacy - they are likely to be rare given the scarcity of surface water on Vulcan.190 | Melora |
| Vulcan sandworms417 | Animal lifeform native to the planet Vulcan. Phlox fed them to his Pyrithian bat.417 | Regeneration |
| Vulcans9 | Major Alpha/Beta Quadrant power.9 Borg designation Species 325959 | Amok Time |
| Wadi448 | One of the first Gamma Quadrant species to come through the wormhole, the Wadi are very interested in games.448 | Move Along Home |
| Wanoni Tracehound42 | Predator noted for its persistence42 | The Forsaken |
| Web Creature181 | This creature lived on an alpha quadrant planet. The hole being was enourmous, but any part of it could operate as an individual life form.181 | Vox Sola |
| Wentlian Condor Snake30 | Life form known as a delicacy30 | Business as Usual |
| White Rhinos67 | Terran animal67 | New Ground |
| Wise ones363 | Another name for the Preservers363 | The Paradise Syndrome |
| Wisps449 | Non corporeal species encountered by the NX-01 Enterprise in 2152. The Wisps were once corporeal beings much like Humans, and were able to posess Human bodies. They lived in subspace and could pass through most solid substances, but not Osmium alloy.449 | The Crossing |
| Wogneer Creatures95 | Creatures which reside in the Ordek Nebula. Captain Picard once risked his life to help the Wogneer creatures.#4065} | Allegiance |
| Wompat303 | Rodent native to Cardassia303 | Chain of Command, Part 1 |
| Wraith98 | These shape-shifting creatures lived on a rogue planet. They were sentient telepaths, but the Eska hunted them for sport.98 | Rogue Planet |
| Wysanti450 | Delta Quadrant species encountered by Voyager.450 | Imperfection |
| Xanthan marmots347 | Species to be found in the Delphic Expanse. They make excellent pets and are also very tasty.347 | Rajiin |
| Xantoras38 | Species which inhabited the planet Xantoras. The Xantoras government tended to be quite unstable, and rapid changes in the political structure were not unusual. In 2153 a military government demanded that all aliens leave the planet at once; the NX-01 Enterprise rescued a party of Denobulan geologists from the planet.38 | The Breach |
| Xarantine451 | Species which the Klingons raided in 2151.451 | Sleeping Dogs |
| Xelatians452 | Species present in the Federation council in 2285.45 | Star Trek IV : The Voyage Home |
| Xenon based life form400 | Life form whose chemistry is based on the element xenon400 | Hope and Fear |
| Xepolites366 | Humanoids who smuggled weapons into the demilitarised zone for the Cardassians.366 | The Maquis, Part 2 |
| Xyrillians453 | Advanced species discovered by Enterprise in 2151. The Xyrillians pass a mild electrical charge when touched. Their males carry the offspring, who only have DNA from the mother.453 | Unexpected |
| Yadera454 | The Yadera are a holographic race created by an unknown species. They were unaware of their true nature until the holographic generator began to break down.454 | Shadowplay |
| Yak Bear429 | Large animal native to the planet Gaia429 | Children of Time |
| Yallitians377 | Species native to the Delta Quadrant377 | Phage |
| Yalosians205 | Sentient life forms205 | Improbable Cause |
| Yangs280 | Humanoids native to Omega IV; enemies of the Khoms280 | The Omega Glory |
| Yattho455 | Beta Quadrant civilisation455 | Before and After |
| Yridian Yak456 | Grazing animal known for its size456 | Accession |
| Yridians457 | Humanoid civilisation known as information dealers.457 The Yridians were thought to be extinct by the Federation and the Borg, until contacted by Captain Ransom whilst he was working as an exo-biologist.35 | Birthright, Part 1 |
| Zahl19 | Delta Quadrant civilisation eradicated by the Krenim in an alternate timeline19 | Year of Hell, Part 1 |
| Zakdorn458 | The Zakdorn are considered master strategists, a reputation so fearsome that nobody dares to attack them.458 | Peak Performance |
| Zaldan84 | The Zaldan have webbed fingers and are infuriated by courtsey, which they believe is a form of dishonesty.84 | Coming of Age |
| Zalkonians459 | Humanoid species which have begun to evolve into a noncorporeal state459 | Transfigurations |
| Zan Periculi12 | Species native to the Ferengi planet Lappa IV12 | Menage a Troi |
| Zeons186 | The Zeons where pesicuted by the Ekosians.186 | Patterns of Force |
| Zetarians460 | Non-corporeal species whoattacked the Federation databank at Memory Alpha. 460 | The Lights of Zetar |
| Zevians352 | Civilisation who requested some information on a smuggling ring from DS9352 | His Way |
| Zibalian290 | Humanoid civilisation noted for facial tattooing. A Zibalian once attempted to kidnap Data.290 | The Most Toys |
| Zylo Eggs111 | Life form which Data attempted to paint to test his creativity111 | 11001001 |
| Yellow text = Canon source | Green text = Backstage source | White text = DITL speculation |
References