Captain Jippeq, a male Varro in 2375
Varro script
The Varro were a xenophobic humanoid species encountered by the USS Voyager while it was in the Delta Quadrant.
Biology
Physiologically, Varro were humanoid with their only known external difference from Humans being a series of horizontal ridges down the back of their neck and along their spine.
Varro traditionally mate for life. When two Varro have intimate relations, they experience olan'vora n– "the shared heart". This makes their body chemistry interdependent, causing withdrawal symptoms if the two people separate. The effect gets stronger with each coupling, and prolonged separation from their mate can literally be fatal for a Varro.
Overview
In the 1970s, the Varro launched a ship of exploration. As years went by, the ship became generational, and expanded. Originally one segment, they built more and more, until the generational ship was much larger.
The nature of the generational ship meant that the Varro society developed into a semi-oppressive regime where contact with other cultures was avoided at all costs and the will of the individual was subservient to the will of the group. This led to the founding of a rebel group within the Varro who introduced silicon parasites into the ship to separate the various sections so each could go their own way.
In 2375, the Varro generational ship experienced heavy problems with their warp engines as a result of the virus. Luckily, they came across the USS Voyager, who gladly offered assistance. After two weeks, Voyager's team discovered the parasites that were eating away at the hulls of both ships. They were able to stabilize the ship long enough to evacuate the affected sections but the generational ship broke up.
Most of the Varro chose to stay together and continue their exodus but a small number of the sections went their own way. (VOY: "The Disease")