Overview
In the Northern Hemisphere carnids are usually associated with bird nests or rodent burrows, in which their (probably) saprophagous larvae live. The only certainly Australasian genus,
Australimyza
, lives on the seashore or nearby salt flats.
Description
Carnids are very small, stout, greyish or dark-coloured flies. Australasian species have the following features:
Postocellar bristles nearly parallel; three orbital bristles, with the anterior one directed inwards; vibrissa present, together with another large bristle close behind it; face sclerotised and concave; first flagellomere drooping and without long setae on anterodorsal margin (compare to Xenasteiidae); proboscis moderately short, with broad labella (compare to Milichiidae); anepisternum bare; katepisternum with two large upper bristles; prothorax without precoxal bridge; tibiae without preapical dorsal bristle; vein C with both humeral and subcostal breaks; vein Sc well sclerotised, but fading distally near vein R1; cells bm, dm and cup enclosed; vein A1+CuA2 long, but incompletely sclerotised; alula well developed, with marginal fringe of short setulae.
Distribution
Carnids have a wide, but apparently scattered, world distribution. The subfamily Australimyzinae lives in New Zealand and temperate Australia, including one species on Macquarie Island. This group is sometimes treated as a separate family. Populations on mainland Australian perhaps represent a single undescribed species, but have not yet been studied in detail.