Recognition and palaeohydrologic significance of fossil black fly larvae,with a key to the Nearctic genera (Diptera: Simuliidae)

Fossil black fly larvae of late Pleistocene and Holocene ages are reported from lacustrine deposits of coastal British Columbia, including the first record of the genus Parasimulium Malloch from Canada. Features that distinguish fossil larvae from the remains of other organisms are reviewed, and a key to the Nearctic genera based on features of the hypostoma presented. Fossil black fly larvae have potential for providing information about changes in fluvial conditions, and provide direct evidence about the composition of past faunas. The palaeohydrologic significance of late Quaternary assemblages from coastal British Columbia is discussed.