Piranha locust

Piranha locusts were hornet-like insects of the planet Bliss. They were several times larger than normal. They were a dangerous flesh-eating insects. A swarm of Piranha locusts encountered the Seventh Doctor, Ace and Hex. The DNA of the insects was combined to that of the Silkworms by Professor Toshio Shimura to create a metal-eating parasites called the kiseibya. (AUDIO: Enemy of the Daleks)