Diagnosis of the clarki -group

The clarki -species-group can be separated from all other Australian Calliphorinae by the presence of (1) a reduced anterior spiracle, smaller at widest part than width of proepisternum (Fig. 3C, D); (2) hyaline or lightly coloured upper calypter with contrasting dark brown or orange fringe in combination with an infuscated lower calypter (Figs 1E, 4E); (3) postpedicel at least partially orange (Figs 1B, 2B, 3B); and (4) male terminalia with weak or no sclerotisation in distal part of mesohypophallus (Figs 2H, 4F, 5H). The species of this group were previously placed under the genera Onesia and Calliphora .

Key to species of the clarki species-group

Abbreviations for states and territories are provided within couplets for species that are restricted to specific regions of Australia.

1. Basicosta ground colour black (Figs 4E, 5E) ................................................................................... 2

– Basicosta ground colour brown, orange or yellow (Figs 1E, 2E) ..................................................... 4

2. Arista plumose, 1.5 × postpedicel length (Figs 4C, 5C); NSW ........................................................ 3

– Arista almost bare, with only a few very short and sparse setulae near base, 2.0 postpedicel length (Fig. 3C); TAS ..................................................................................................... C. ignicera sp. nov.

3. Acrostichal setae 2+2 (rarely 2 +3); abdominal tergites ventrally with very weak or no microtomentum; pleural suture between anepisternum and anepimeron not pronounced, similar in colour to surrounding structures (Fig. 4E); males only, cercus appears hook-shaped in lateral view, with only very slight concavity in its basal half (Fig. 4F); NSW ......................................... C. niveata sp. nov.

– Acrostichal setae 2+3 (Fig. 5A); abdominal tergites ventrally with grey microtomentum that changes colour with viewing angle; pleural suture between anepisternum and anepimeron pronounced, convex and dark red-brown, distinct from ground colour of pleura (Fig. 5E); males only, cercus with strong concavity in its basal half (lateral view) (Fig. 5F); NSW, VIC C. xanthocera Malloch, 1927

4. Males only, fronto-orbital and parafacial plate mottled gold at the height of antennal insertion (Fig. 2A–B); ACT, NSW, VIC ................................................................................ C. ampyx sp. nov.

– Males only, fronto-orbital and parafacial plate grey, silver, white or black at the height of antennal insertion (Fig. 1A–B)......................................................................................................................... 5

5. Pleural suture between anepisternum and anepimeron pronounced and dark red-brown, distinct from ground colour of pleura (Fig. 5E); NSW, VIC ..................................... C. xanthocera Malloch, 1927

– Pleural suture between anepisternum and anepimeron not pronounced and similar in colour to surrounding structures (Fig. 1E); WA ........................................................... C. clarki Malloch, 1927