Alderfly
Sialis lutaria
ok. 10 mmAdult female
Body length
Body length
od przodu głowy do końca odwłoka · bez czułków, nóg i wystających skrzydełMeasurement: side
Alderfly — size comparison
The alderfly Sialis lutaria is a dark insect with densely veined wings held roof-like over its body at rest. Adults occur beside standing and slow-flowing water
Silhouette comparison
Length
od przodu głowy do końca odwłoka · bez czułków, nóg i wystających skrzydełScale for the stated dimensions · each animal is labelled
Measurement comparisonScale in cm
0246810
approx. 10 mm
8.56 cm
The scale compares the named dimensions. View direction and measurement points are given for each animal.
Alderfly — size comparison — facts and sources
The alderfly Sialis lutaria is a dark insect with densely veined wings held roof-like over its body at rest. Adults occur beside standing and slow-flowing water. They usually stay close to shore, resting on plants or other surfaces near their development sites.
The adult stage is short and is not devoted to intensive feeding. The female lays eggs where the young can reach water.
Larvae are predatory, with strong jaws for catching small invertebrates. After living underwater the larva comes onto land to pupate. Different alderfly species can look very similar, and water-body type is only a clue.