Arcturan
Arcturans were a species of aliens which resembled a skull with tendrils spreading out. In order to survive outside their own planet, they require life support systems. The most vital system is the helium regenerator. (DW: The Curse of Peladon) These systems would range from simple boxes with a necessary equipment to advanced systems capable of travelling and surviving nearly anywhere. Though the Arcturans knew of the Doctor, records of him were scarce. (NSA: The Doctor Trap)
The Semblance of Draxyx was an Arcturan and a member of the Endangered Dangerous Species Society. He was one of the member who arrived and was killed on Planet 1. (NSA: The Doctor Trap) During Peladon's entry into the Galactic Federation, the Arcturan delegate, Arcturus, betrayed the other ambassadors. (DW: The Curse of Peladon)
The Doctor once reminisced about the time he, Rose Tyler and an Arcturan shared an experience in a cellar. (BBCR: The Day of the Troll)