ARNOR / DREAD LORDS

Planet of Origin: Amalda in the Amaldia system
The Arnor were a powerful civilization that existed millions of years ago and which got politically divided in two factions, one calling themselves Arnor, the other one, Dread Lords. As the Dread Lords were on the brink of conquering the galaxy, the Arnor , on the brink of extinction, sealed them away into a pocket universe. It remains unknown what happened to them afterward.
Source: Galactic Civilizations

ALTARIANS / DRATH

Planet of Origin: Altaria, a planet orbiting Altaris. Relocated to Dratha in the Drathis system after a war with the altarians.
The Drath Legion is a reptilian civilization that was nearly wiped out by their homeworld's other more numerous sentient species, the Altarians during a dominance war and who consider themselves the true Altarians. The Drath are passive-aggressive manipulators, remaining hidden and pulling the strings on the weak and powerful alike with subtlety in mind and seemingly infinite patience.
Source: Galactic Civilizations

APLANS

Planet of origin: Alfava Metraxis, the seventh planet orbiting Dundra, in the Gan belt.
The Aplans are a peaceful bicephal humanoid species. Each heads has its own intelligence and personalities. They are prolific builders, and erected notable landmarks including the Aplan Mortaria, sometimes known as Mazes of the Dead, large subterranean labyrinths with tombs in the walls, adorned with statues of the dead. The Mazes hassix levels, representing the ascent of the soul in the Aplan religion. The Aplans adept at recording their social, cultural and political history.
In the 47th century, a large population of Weeping Angels came to Alfava Metraxis and hunted the Aplans to extinction, the Angel colony lacked any further energy source and over the centuries, the being energy deprived began to degrade and went into hibernation. After the Angels fell into a Crack in Time in the 51th century, they stopped existing, which means the Aplans could still be existing.
In the 49th century, the planet was terraformed by human settlers. As a result, the atmosphere boasted a high level of oxygen and a low amounts of toxins. It had an oxygen-rich atmosphere, and an eleven-hour day. During the 49th century, humans terraformed the planet and by the 51st century, six billion settlers had come to live there.
Source: Doctor Who universe, (DW: The Time of Angels)

SATURNYNIANS

Planet of Origin: Saturnyne, an earth-type planet with huge bodies of water.
The Saturnynians are amphibians with fish and crustacean traits, They have a vaguely humanoid upper body, a fishlike head with sharp teeth and lobster-like lower body. They have a strong sensitivity to ultraviolet light, being repelled by smaller amounts and being incinerated by large amounts.
They are capable of converting some other species (like Humans) into Saturnynians by draining them of their blood and replacing it with their blood.
Some time in the species' history their home-world was besieged by the cracks in the universe, ranging from small cracks to cracks that consume the planet's sky. At first the cracks appeared to pose no real danger and the aliens were able to observe other worlds through some of them. Eventually, however, the true nature of the cracks became apparent and Saturnyne was lost. Some took their chances with the cracks that showed other worlds and fled to worlds with oceans like their own planet. One colony made it to Venice in 1580 but was only able to survive on Earth for a short while.
Source: Doctor Who universe (DW: The Vampires of Venice)