Immature Stages of Osmylidae
Detailed information on immature stages of Osmylidae is being acquired. However, Withycomb (1923) and Killington (1936) studied Osmylus fulvicephalus Scop., and reported that the larvae are amphibious and probe into the mud with their long slender mandibles for the larvae of Chironomus and other Diptera in the wet, mossy borders of streams and the like. The eggs are elongated and oval, somewhat flattened, with the chorion bearing reticulate markings, and the micropyle is knob-like. They are laid in rows on some object near the water=s edge. Hatching occurs in ca. 22 days, and larval maturity is reached the following spring. The cocoon is spun in damp moss and the adult emerges 10-12 days later.
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