The Koltaari are a humanoid species native to the planet of the same name in the Beta Quadrant. Their skin runs through a range of green shades, similar to the Orions, and their eyes typically have large, golden irises with vertical, almond-shaped pupils. Most Koltaari have blonde hair, worn long. (Star Trek: The Lost Era novel: Serpents Among the Ruins)
In the early 24th century, the Koltaari were still a prewarp civilization and had reached a technological level roughly equivalent to that of mid-21st century Earth, with egg-shaped hovercars among their inventions. They lacked both the technology and the desire to harvest the many rare minerals found on their planet, but those resources nonetheless made them a target for interstellar agression. Their planet was invaded by the Romulan Star Empire in 2311, shortly prior to the Tomed Incident, and the Koltaari were used for slave labor during the occupation.
The Romulans withdrew from Koltaari in the aftermath of Tomed, and the planet became a Federation protectorate, and started to receive aid to rebuild their world and help them transition into the galactic community after such a tragic first contact. (TLE novel: Serpents Among the Ruins)