- You may be looking for another species of the same name or the Arcturans.
Arcturians were a humanoid species native to the planet Arcturus. They wore grey metallic clothing and resembled "magnificent specimens of early Greek manhood". They did not breathe oxygen, with the Doctor supposing that they instead breathed ammonia and methane.
In 1872, Arcturians were a spacefaring humanoid species. They sent a research vessel to Earth in that year, where they captured specimens of humanity in the form of the crew of the Marie Celeste. They also captured the crew of the Tardis, the Second Doctor, Jamie McCrimmon and Zoe Heriot, who escaped by exposing the ship's sole crewmembers Eretz and Lantis to oxygen, killing them. The ship was later attacked by a sea serpent, which dragged it to the bottom of Earth's ocean. (PROSE: The Mystery of the Marie Celeste [+]Loading...["The Mystery of the Marie Celeste (short story)"])