Tarchannen III

Tarchannen III is the third planet in its system, located in Federation space. The planet is home to a non-sentient species, which had a mimetic ability that made them nearly invisible.

The planet itself is characterized by perpetual twilight, frequent sandstorms and its sparse vegetation, including a variety of dark, spindly plants.
The planet's atmosphere stretches up to an altitude of 210 kilometers.

A Starfleet outpost consisting of at least five buildings was located on the planet, until the whole crew of 49 disappeared in 2362.
Their disappearance was investigated by an away team from the USS Victory, who concluded that the outpost showed no signs of an attack or a natural disaster – the people had just "vanished."

It was not until 2367 that this mystery could be solved. Three members of the former away team suddenly deserted and attempted to return to the planet, and one was killed in this attempt. While the USS Enterprise, NCC-1701-D was investigating these incidents, two crewmembers underwent a strange transformation. While one transformed crewmember managed to transport down to the planet, it was discovered that the transformation was caused by a parasite. This parasite planted its DNA into living hosts to reproduce itself, and the hosts then transform into a primitive reptile-like species, with the overwhelming urge to return to Tarchannen III.

Following this discovery, warning beacons were placed in orbit and on the surface of the planet to prevent similar incidents in the future.