Vissian
The Vissians were a highly advanced (by Human standards in the 2150s) humanoid species native to the planet Vissia in the Vissia system.

Morphology

Vissians were distinguishable by crescent-shaped, segmented ridges circling the eye at the temple. Unusually (by Human standards) the Vissians had three genders: male, female, and cogenitor. The third gender, cogenitors, made up only 3% of the population and were treated as inferior, existing only for facilitating reproduction between males and females.

Vissians were able to read, learn, and retain large amounts of new information much more quickly and easily than Humans.

History and technology
The Vissians claimed to have developed warp drive around the 12th century.

In the 2150s, Vissian space travel utilized superior warp core and sensory technology compared with Humans. They were also using photonic weapons, rechargeable with sarium microcells. 

The Vissians claimed to have developed a polymer composed of over two hundred natural elements. At that time Humans were only aware of 92.

At least one ship type was capable of withstanding temperatures higher than 11,000 degrees to withstand exploration within a stellar corona. Their stratopods were able to pass through the hydrogen layer of a hypergiant.

The Vissians offered to modify 's sensors to detect nucleosynthesis.

 Vissian starship
 Vissian stratopod

Culture and philosophy

Vissian appreciation of food was based on aroma rather than taste. Of Human foods tried, they tended to like varieties of cheese.

Vissians were more forward and liberal than Humans were with regards to copulating. They preferred to have sexual intercourse first before continuing a relationship. 

Vissians tended not to travel far, believing that there was sufficient exploration close to their homeworld: this is the reason why they had not expanded particularly far from their homeworld, despite possessing warp drive far longer than Humans had. Their primary goal was to meet new species. They were willing to share their technology with the Enterprise. 

Despite being unknown to Humans and Vulcans by the 22nd century, their language was immediately picked by the Enterprises universal translator. ()

People
 Calla
 Charles
 Drennik
 Traistana
 Veylo
 List of unnamed Vissians

Apocrypha
In the novel To Brave the Storm, Captain Archer unsuccessfully tries to convince the Vissian government to assist Earth during the Earth-Romulan War.

In the ebook The Future Begins, there was a Vissian woman serving in the Starfleet Corps of Engineers in the 24th century.

External link
 

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Species