Higher species

"Higher species" or "higher forms" was a term used to refer to species who were aware of the Time Lords and the Last Great Time War. Doubting the Tenth Doctor's identity as a Time Lord, the Shadow Architect stated that the Time Lords were the "stuff of legend" and that they belonged in the "myths and whispers" of the higher species. (TV: The Stolen Earth)

According to the Gelth ambassador, the Last Great Time War was devastating to "higher forms" yet invisible to "smaller species," (TV: The Unquiet Dead) the War Master noting that the higher beings were aware of the danger to reality. (AUDIO: Concealed Weapon)

Awareness
Even before the Time War, the Time Lords were known to several races and beings, including the Osiran Sutekh (TV: Pyramids of Mars) and the Daleks. (TV: Resurrection of the Daleks) The Cybermen were aware of the Time Lords and that they were forbidden to interfere, (TV: Earthshock) while Sabalom Glitz suspected the Sixth Doctor of acting on their behalf. (TV: The Mysterious Planet)

Having been caught in their Time War, the Time Lords were recognised by the Nestene Consciousness, (TV: Rose) the Gelth, (TV: The Unquiet Dead) and the Bygone Horde. (AUDIO: The Other Side)

In 1980, the Fisher King described the Time Lords to the Twelfth Doctor as "cowardly, vain curators who suddenly remembered they had teeth and became the most warlike race in the galaxy." (TV: Before the Flood)

In 2007, Brother Lassar of the Krillitanes was aware of the Time Lords and their apparent extinction. (TV: School Reunion)

In 2010, the Shansheeth recognised the Eleventh Doctor as the last of the Time Lords. (TV: Death of the Doctor) After news of the Doctor's death at Lake Silencio in 2011 spread, recognised her new position as "the last of the Time Lords." (AUDIO: The Bekdel Test)

The time travelling Family of Blood recognised the Tenth Doctor as the last of the Time Lords. (TV: Human Nature / The Family of Blood)

Shortly before his death in 4221, the Beast branded the Tenth Doctor as "the killer of his own kind". (TV: The Satan Pit)

By the Siege of Trenzalore, "half the universe" lay in wait over Trenzalore, ready to restart the Time War had the Time Lords returned. They included Daleks, Cybermen, Weeping Angels, Sontarans, Terileptils, Slitheen, Silurians, Judoon, Ice Warriors, Krynoids, Nestenes, Shakri, Krotons, Mara, Monoids. The Church of the Papal Mainframe, which included humans and Silents, fought in defence of the planet alongside the Eleventh Doctor. (TV: The Time of the Doctor)

By Earth Death in 5,000,000,000, Jabe of the Forest of Cheem was aware of the apparent extinction of the Time Lords at the end of the Time War, and was surprised when she found that the Ninth Doctor was one. (TV: The End of the World) The Face of Boe also knew the Tenth Doctor to be a Time Lord. Immediately prior to his death in 5,000,000,053, he informed the Doctor, who believed himself to be the last of his kind at the time, that he was not alone. (TV: Gridlock)