Intelligent Lifeform Index

Four Letter Code EFRO
Federation Status Member
Planet of Origin
Encountered ST:IV The Voyage Home
T/E Rating T0/E0
Current Tech Level N
List of Named Efrosians

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The Efrosians are a humanoid species native to the planet Efros, located in the Flarset system.

Home System

  • Quadrant:
  • Location: Federation space
  • Proper Name: Flarset system
  • Star:
  • Distance from Star:
  • Companions: Efros is the last of four planets
  • Moons: 2[1]

Home World

  • Proper Name: Efros
    • Other names: Flarset IV, Efros Delta
  • Diameter: 14,300 kilometres
  • Gravity: 1.1 standard gravity
  • Axial Tilt:
  • Orbital Period:
  • Rotational Period: 29 hours
  • Classification: M
  • Surface Water: 64%
  • Atmosphere:
  • Climate: In the throes of an ice age ("Efros" literally translates to "ice" in the Efrosian language)
  • Terrain: Massive glaciers dot the landscape[2]
  • Population:


Some anthropologists claim there is evidence that Efrosians did not evolve on Efros.

Efrosians contrary to many religious oligarchies believe that technology improves life and as the climate warmed, additional resources were discovered furthering their technological progress.

Prior to first contact with the Federation, the Efrosians were under Klingon rule but they led a revolution against them.

First contact was made in 2278 when the Vulcan crew of the USS Surak visited Efros. The Efrosians soon joined the Federation and began many exchanges with other worlds. They commonly serve as helmsmen and medical personnel.

The United Federation of Planets made first contact with Efros in 2278. Since then, the Efrosian people have firmly cemented themselves as citizens of the Federation. Most notably, an Efrosian served as President of the Federation in 2293.


Each tribe during their ice age had one warrior-priest who was someone who had great martial skill as well as healing. When this ice age ended, the warrior-priests united into a religious oligarchy.


Efrosian males had cranial ridges and were generally seen wearing long, white hair and flowing mustaches.[3] Males tend to have white or blonde hair while females usually have black or dark brown hair. It is typical in Efrosian culture for the males to grow lengthy mustaches, and most Efrosians wear their hair long.


Efrosians are similar in appearance to Klingons but compared to Klingons, their cranial ridges are less distinguished. They have inherited fatty deposits on their faces which are inherited from their ancestors who did not cover their faces on the cold planet of Efros. Males have white/blonde hair whereas females tend to have black/dark-brown hair. The digestive tract of Efrosians contains two stomachs and they need the oils from Levithi nuts (native to Efros Delta) to maintain healthy. They have bad eyesight which is compensated with a heightened sense of smell. Despite this eyesight, they have a wider range of vision than humans. As well as this, they are well known for their sense of direction as a result of the heavy snowstorms native to Efros.


Efrosians are often attuned to others' emotional needs, and considered an emotionally complex people.


Efrosians are deeply spiritual and their religion focuses on binary morality (good & bad) as in many Earth religions. Heaven is known as 'Endless Sky,' and it balanced by an underworld. Funeral services feature a death march in honour of the deceased. Efrosians refuse to discuss their religion with outsiders so therefore there is much speculation about the religion.




Efrosian culture is the result of living on the harsh, frozen world of Efros for generations. Both technological and social development were minimal during the millennia-long ice age that ravaged the planet. Close-knit tribes formed out of a need for survival. Once the immense glaciers began to break up, the planet eventually united.

Children are raised by their mothers alone -- the Efrosian word for mother is the word which translates into English as "parent". Most Efrosians never meet their father.[4]

Efrosians are also known for their dedication to oral history and as well for their musical language. They do not have a written language but instead memorize history and their libraries resemble music archives more.

They lack the concept of monogamy but this doesn't mean they are promiscuous. However, they find sexual intercourse to be a good way to learn to work with others but it is seen as rude to flirt with someone of your preferred sex. Most Efrosians are only raised by their mother as on Efros Delta, it was necessary for males to mate with as many females as possible.

Naming conventions

Efrosians often have hyponated names, using a combined convention, and is considered neither a first name nor a last name. For example, Ra-Uleyra's name represents his father's linage ("Ra'), but "Uleyra" is unique entirely to himself. To address an Efrosian by only the second half of their name is considered offensive.

Females will chance the first half of their name when attached, but as they may have several mates over their lifespan, it's a general practice to change their name many times throughout their lifespan.[5]




Starfleet Intelligence Files


  1. Flarset system, Memory Beta
  2. Efros, Memory Beta
  3. Efrosian, Memory Alpha
  4. Efrosian, Memory Beta
  5. Ra-Uleyra