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Related to alderfly: Sialis lutaria, Fishfly


Any of various insects of the family Sialidae, having two pairs of dark many-veined wings, long antennae, and aquatic larvae.

[Probably so called because the mature insects can be found resting on foliage in the moist habitats near lakes and streams where alders typically grow.]


(Animals) any of various neuropterous insects of the widely distributed group Sialoidea, such as Sialis lutaria, that have large broad-based hind wings, produce aquatic larvae, and occur near water
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.alderfly - dark-colored insect having predaceous aquatic larvaealderfly - dark-colored insect having predaceous aquatic larvae
neuropteran, neuropteron, neuropterous insect - insect having biting mouthparts and four large membranous wings with netlike veins
genus Sialis, Sialis - type genus of the Sialidae
References in periodicals archive ?
Alderfly (Neuroptera: Sialidae) flight periods, sex ratios, and habitat use in a Virginia freshwater tidal marsh, low forest, and their ecotones.
The Austroriparian Province contains at least three species of alderfly; S.
NEUROPTERA (alderfly) Sialis americana X X X ODONTATA (damselflies) Argia sp.