Overview
Platystomatids live in most kinds of natural and many human-modified habitats. Adults of numerous taxa feed on fresh mammalian faeces.
Larval habitats are varied, with some larvae living in plant trunks damaged by other insects or fungi, or in coleopterous (beetle) tunnels in fallen logs. At least some
Rivellia
larvae live in bacterial root nodules on leguminous plants, probably including
Acacia
. Larvae of
Elassogaster linearis
(Walker) have been found consuming the eggs of
Locusta migratoria
(Linne), but also live in decaying vegetables. Larvae of
Lenophila
species have been found in damaged trunks of
Xanthorrhoea
(Xanthorrhoeaceae) and
Macrozamia
(Zamiaceae), and adults are commonly found on foliage of the former.
Description
The main diagnostic features include:
Wing vein R1 setulose above; vein C without subcostal break; wing cell cup not acutely produced; incurved lower orbital bristles absent; ocelli well developed; pro-episternal bristle replaced by a group of minute hairs; abdominal sternites 1 and 2 separated by intersegmental membrane; in female, tergite 6 usually much reduced and largely concealed in dried specimens; in some genera, the lower calypter (squama) is remarkably large, resembling that of many calyptrate Muscoidea. In the tropical genus
Achias
, males of several species have the eyes on stalks or lateral extensions of the head capsule.
Distribution
The family, though nearly worldwide in distribution, has its greatest representation in the tropics and subtropics of the Old World and is particularly diverse in New Guinea. Platystomatids live almost throughout Australia, including Central Australia and Tasmania. Our most species-rich platystomatid genus is
Duomyia
, which is endemic to Australia and includes over 100 or our 280 species.