Family Scirtidae

Abstract

Scirtidae (commonly known as "marsh beetles") are the most speciose family of the superfamily Scirtoidea, with over 1,800 known species. They are distributed world-wide, being more common in tropics and the temperate part of the Southern Hemisphere. In the neotropical region, ca. 200 species, classified in 10 genera and two subfamilies, are known. Scirtid larvae inhabit a wide range of aquatic habitats, including lowland ditches, ponds, microhabitats within rivers and streams, phytotelmata, and groundwater as deep as 10 m. Some larvae are terrestrial and live in wet soil or moist, rotten logs. Larvae go through 9-12 instars, are detritivores, and can be easily recognized by their multisegmented antennae and their complex filtering apparatus composed of mandibles, maxillae, hypopharynx and epipharynx. Pupation usually occurs in damp soil, freely exposed or covered. Adults are terrestrial, usually inhabit in riparian vegetation, are generally short lived, and commonly feed on pollen. They are relatively soft-bodied, usually finely pubescent, slightly flattened to very convex, ovate to elongate, and range between 1-15 mm long. In this chapter we present a brief outline of the ecology and systematics of marsh beetles, and provide useful illustrated characters to identify the known larvae of the neotropical fauna.