Many of the most memorable Star Trek aliens debuted on the TV shows, but a handful of classic alien races made their first appearance in the movies. Airing its first episode in 1966, Star Trek: The Original Series represented a major shift in science fiction because of its emphasis on a utopian view of the future. The crew of the USS Enterprise was made up of humans from various backgrounds, and even featured a few aliens as well. Unlike other sci-fi franchises, Star Trek‘s aliens were diverse and weren’t always the villain of each episode.

Though there were plenty of warlike races, like the Klingons or Romulans, a key part of Star Trek‘s philosophy is that people are fundamentally good, even if they are from another planet. Though this morality would get muddier as the franchise progressed, the basic concept behind creator Gene Roddenberry’s vision remained intact. The Star Trek TV shows broke new ground and established the lore, but it was the Star Trek movies that introduced the franchise to a much larger audience. As such, the movies introduced their fair share of aliens, some of which would return for future episodes and films.

10

Arcturians (Star Trek: The Motion Picture)

A Background Alien In Star Trek’s First Movie

The Arcturians are one of the franchise’s more obscure alien species, and their first appearance came in a blink-and-you-miss-it moment in The Motion Picture. Known for their pink and wrinkled skin, an Arcturian appears in the muster scene in the first Trek movie. However, the unnamed character is only seen briefly peaking over the shoulder of another character. Their backstory reveals they are militaristic and rely on cloning to increase their population. It would take decades for another Arcturian to appear in Star Trek, but they would return for four episodes of the animated series, Star Trek: Lower Decks.

9

Keenser’s Species (Star Trek 2009)

One Of Trek’s Few Unidentified Alien Life Forms

The 2009 Star Trek movie introduced the Kelvin timeline and a handful of new aliens as well. Keenser is an alien of an unknown species who works as an engineer and sidekick to Montgomery Scott. The small alien would return for all three Kelvin timeline movies, though almost nothing was revealed about him in the films themselves. In the non-canon comic books, Keenser’s species is revealed to be called the Roylan (likely a reference to actor Deep Roy who played the character), but that hasn’t been confirmed in canon sources. Keenser’s species also hasn’t appeared outside the Kelvin universe.

8

Arcadians (Star Trek IV: The Voyage Home)

An Obscure Member Of The Federation

The Star Trek movies had higher production budgets than the TV shows, so the costume designers were free to create a myriad of background aliens to fill various scenes. The Arcadians are only seen once in Star Trek IV: The Voyage Home, but their doll-like face and reverse mohawk hairstyle make them one of the franchise’s oddest-looking creatures. Little is known about the species from canon sources, but they are an official part of the Federation.

Arcadians have been largely absent from the franchise since their onscreen appearance in Star Trek IV, but they did have a brief cameo in the Lower Decks episode, “An Embarrᴀssment of Dooplers”. In that episode, they were redesigned to have purple skin and less prominent hair. Arcadians were also depicted on playing cards in the Discovery episode, “All In”.

7

Son’a (Star Trek: Insurrection)

The Primary Antagonists Of Star Trek: Insurrection

The Son’a are a unique alien race because they only appeared once, but were a major part of Star Trek: Insurrection. The main antagonists of the Next Generation movie are actually an offshoot of the Ba’ku, the peaceful people who live on the eponymous planet. However, lacking the restorative properties of their homeworld, the Son’a turned to more and more far-flung means to maintain their youth and vitality.

Because the Son’a’s attempts to take over the Ba’ku homeworld failed, they were ostensibly never seen again in mainstream Star Trek canon. The Ba’ku were mentioned in the Deep Space Nine episode, “Penumbra”, but that was mostly parallel with the events of Insurrection. In the alternate timeline created by Q in Star Trek: Picard, the Son’a Empire becomes a major player in galactic events.

6

Chameloids (Star Trek VI: The Undiscovered Country)

Star Trek’s First Shapeshifting Alien Race

A few years before Constable Odo would appear as the franchise’s first Changeling on Deep Space Nine, the shapeshifting aliens known as Chameloids made an appearance in Star Trek VI: The Undiscovered Country. Imprisoned alongside Kirk and McCoy by the Klingons, Martia is a Chameloid who frequently uses her shapeshifting abilities to trick the guards, other inmates, and eventually the Starfleet officers. Not much was known about the species for quite some time, though they can mimic all aspects of another being, including their clothes and voice.

Notable Chameloids include:

The Chameloids would eventually resurface in Star Trek: Section 31 with the introduction of Quasi. Like Martia, Quasi has yellow eyes while in his humanoid form, though it is revealed that a Chameloid resembles a pile of tubes in their natural state. Thus far, a Chameloid has never appeared in any of the Star Trek TV shows.

5

Nibirans (Star Trek Into Darkness)

A Primitive Alien Species From The Kelvin Universe

Most of the aliens that are shown in Star Trek are technologically advanced, but the Nibirans are a rare exception. The primitive species encountered the Kelvin timeline Enterprise when it conducted a mission to save them from an erupting volcano. They are shown as having chalk-like skin, and completely black eyes that lack any pupils.

Little is known about their culture, though it is shown that they have writing. They even sketch the Enterprise, implying that they worship it as some sort of deity. Because the species isn’t sufficiently advanced, Kirk’s mission to save them is the only time that the Nibirans have been shown in the franchise, and it will likely be centuries before they are candidates for first contact.

4

Efrosians (Star Trek IV: The Voyage Home)

An Efrosian Was The Federation President

The first time that an Efrosian was seen in Star Trek was during the events of Star Trek IV: The Voyage Home. However, two movies later, an unnamed Efrosian would be the Federation President and the subject of an ᴀssᴀssination attempt. The somewhat mysterious alien race is known for their all-white hair, cranial ridges, and long flowing mustaches on the males of the species.

None of the classic Star Trek shows would feature an Efrosian in any capacity, but the franchise’s first female Efrosian appeared in the Discovery episode “Labyrinths”. Hy’Rell was an archivist in the 32nd century, though her appearance added little to the established canon about the Efrosians.

3

Jaylah’s Species (Star Trek Beyond)

A Major Character With No Known Species

The character of Jaylah was introduced as a new protagonist in Star Trek Beyond, and she teamed up with the alternate universe Enterprise crew to defeat Krall. However, Jaylah is an alien of unknown species, and the movie didn’t really reveal anything about where she came from. Stranded on the planet Altamid for most of her life, Jaylah seemingly has no connection to her home planet, whatever that may be.

She has stark white skin and hair, and unique stripe markings that run down her scalp and face. Though she’s shown as being quite adept at martial arts, Jaylah’s species doesn’t exhibit many traits that are uncommon in other humanoid life forms. Since Beyond is, thus far, the final film in the Kelvin timeline, Jaylah has yet to return in Star Trek canon.

2

Remans (Star Trek Nemesis)

The Cousins Of The Romulans

First appearing in the final Star Trek: The Next Generation movie, Nemesis, the Remans are actually cousins of the dreaded Romulans. Immediately identifiable by their pale and hairless skin, the Remans also have pointed ears and fang-like teeth. Being used essentially as a slave-labor force by the Romulans, the Remans have adjusted to working in the low-light conditions of dilithium mines and have incredibly sensitive eyes.

Interestingly, the Remans are also capable of telepathy, and communicate with one another mentally. They are typically stronger than humans, and are capable of great feats of strength in battle. Besides their appearance in Nemesis, the Remans appeared in two episodes of Star Trek: Enterprise, and even made a brief cameo as corpses in Star Trek: Lower Decks.

1

Deltans (Star Trek: The Motion Picture)

Gene Roddenberry Created The Species For The First Movie

Star Trek: The Motion Picture was pieced together using ideas from the never-realized Star Trek: Phase II series, and the Deltan species was one such original creation. First introduced through the character Ilia, the Deltans look almost exactly like humans except they all have completely bald heads. They are intensely Sєxually attractive to others, and therefore take oaths of celibacy before joining Starfleet.

While they cannot heal wounds, they do possess the ability to soothe the pain of others who are injured. In extended lore that was never mentioned in any canon sources, Deltans are described as a mentally-advanced species that is stoic but not unemotional like Vulcans. Deltans have appeared on numerous occasions throughout the rest of the Star Trek franchise, but only as background characters.