Redescription of Cricotopus lebetis (Diptera : Chironomidae), a potential biocontrol agent of the aquatic weed Hydrilla (Hydrocharitaceae)

The adult male and female of Cricotopus lebetis Sublette are redescribed an d the pupa and larva described for the first time. Larvae of C. lebetis min e in the stems of the submersed aquatic weed hydrilla, Hydrilla verticillat a (L.f. Royle), causing sufficient damage to the apical meristem to preclud e further growth. The species is very similar to C. tricinctus (Meigen) but can be distinguished from that species in the adult male by the broader, m ore rounded inferior volsella; in the female by the lower number of sensill a chaetica on the mid and hind basitarsi; in the pupa by the fusiform thora cic horn; and in the larva by the simple S I and long setal tufts on abdomi nal segments I-VII.