Scissor bug
Scissor bugs were an insect which were pests on Gallifrey, (PROSE: Lungbarrow, The Duke of Dominoes) but deadly on other worlds. (PROSE: The Ruins of Heaven)
The Other's rose garden was plagued by scissor bugs when he gave it to Rassilon. (PROSE: Lungbarrow)
When the Master was a student, he once witnessed a cloud of thousands of male scissor bugs in mating frenzy trying to couple with their nest's single queen. The Master smugly watched them die over the course of day, having taken the queen himself and put it in a jelly jar. (PROSE: The Duke of Dominoes) The Seventh Doctor once compared an action to being like a scissor bug escaping a jam jar. (PROSE: The Hunting of the Slook)
An angel once registered 15 million people on Skopta Maxima praying for deliverance from an invading swarm of scissor bugs. (PROSE: The Ruins of Heaven)