Observations on the Limnological Factors Associated with Three Species of the Simulium jenningsi Group (Diptera:Simuliidae) in New York State

A survey of three species of Simulium (S. jenningsi, S. luggeri and S. fibrinflatum) was conducted from April to October, 1978, in the Adirondacks and Finger Lakes region of New York State. These species were distributed within the study area as follows: S. fibrinflatum, Adirondacks; S. luggeri, Finger Lakes region: and S. jenningsi, both areas. All three were found from June through September. Of the 21 limnological parameters studied, the most important in separating the species were pH and ionic concentration of the water. Simulium fibrinflatum occurred in mildly acidic to neutral, dilute streams whereas S. luggeri occurred in basic, rich streams. Simulium jenningsi was found in both types of streams.