Vespiform

Vespiforms were an ancient and wise insectoid species. They had hives in the Silfrax Galaxy.

Biology
Vespiforms were a species of insectoids which resembled oversized wasps. Adults were about three metres tall. They were powerful creatures, with large stingers which could be regrown within hours of use.

Vespiforms could change into other species. The transformations were accompanied by a glowing, purple-pink haze and left behind morphic residue.

When in another form, Vespiforms were genetically compatible with the mimicked species. They could interbreed with members of any other species. Any offspring would be locked in one form until put under stress, when they would turn into their Vespiform shape. (TV: The Unicorn and the Wasp)

Technology
Vespiforms had telepathic recorders. These devices held the essence of the Vespiform cultural heritage, and served as a sort of "instant school". The entirety of what it meant to be a Vespiform could be transferred from the recorder to the mind in a matter of seconds. The device also transferred the thoughts of any being in very close proximity to it as well. Were the thoughts of a non-Vespiform to blend with the information contained in the recorder, the results could be unpredictable. (TV: The Unicorn and the Wasp)

History
Some time prior to Earth's 19th century, the Vespiforms developed intergalactic space travel. This allowed at least one of the species to travel from the Silfrax Galaxy to Mutter's Spiral. At least one Vespiform went to Earth, presumably for the purposes of research. (WC: )

In 1885, this Vespiform (simply known as Christopher) met Clemency Eddison in India and had a child with her. He gave her a large, purple crystal set in a necklace, which she called "the Firestone". When he soon thereafter drowned during a monsoon, the Firestone became her only memory of him, and she wore it often.

Some months later, Clemency gave up their child for adoption; the morés of the time frowned on unwed parents. The child became a reverend, Arnold Golightly, a vicar in the parish that included the Eddison's estate. At the age of forty in 1926, he discovered his Vespiform nature. Because of his proximity to the Firestone — in reality a Vespiform telepathic recorder — his Vespiform cultural heritage was transferred to him from the device. The transfer also included some of its wearer's thoughts. Lady Eddison was reading an Agatha Christie novel at the time of the transfer, so Golightly absorbed some of the aspects of the characters in the novel. Golightly started committing various murders in the style of an Agatha Christie novel. The Doctor, Donna Noble and Agatha Christie herself investigated his crimes, and forced Golightly to publicly reveal his Vespiform nature. Ultimately, Donna killed him by throwing the Firestone into the lake. Golightly followed and drowned, but relieved Agatha of his connection with her in his dying moment. (TV: The Unicorn and the Wasp)

The Sixth Doctor encountered them on Earth, in 1999. (PROSE: Millennial Rites)

Long after the events at Eddison Manor, the Firestone was dredged up from the lake and sold at auction to Jack Harkness. In the 21st century, he claimed to be in possession of the only Vespiform telepathic recorder known to exist on Earth. (WC: )

The Quarks attempted to use Vespiforms to attack the Second Doctor and Jamie McCrimmon on Gano, but the creatures attacked the Quarks instead. (COMIC: The Killer Wasps) Jack Harkness had heard whispers of a war between Quark rebels and Vespiforms, but he could not confirm these stories. (WC: )

A film adaptation of H.G. Wells' The Time Machine, which according to the Sixth Doctor "hadn't even been bad enough to be good", featured Vespiforms and Quarks. (PROSE: Synthespians™)

Behind the scenes

 * According to The Brilliant Book 2012, a book that contains non-narrative based information, Amy Pond and Rory Williams might have encountered some Vespiform in the Gardens of Zul-Thep in the year 3104. (REF: The Brilliant Book 2012)
 * Russell T Davies' original concept for the Shadow Proclamation scene in The Stolen Earth included an appearance by several buzzing Vespiform, but his plans to feature a "rogues gallery" of alien races in the scene fell through; ultimately the Judoon were the only returning race featured.