48 R. W. CROSSKEY 



widened above and contracted ventrally (in latter case not normally formed 

 into a very narrow sharp ridge). Parafacials bare or haired, but if haired the 

 hairing not normally extending below the lowest point of the eye in profile and 

 haired area of parafacials well separated by conspicuous bare area from haired 

 genal dilations ............ 6 



6 Intermediate abdominal tergites without discal setae. Facial carina usually very 

 broad and flattened, often slightly sulcate, with subparallel sides, at most only a 

 little knob-like dorsally and contracted ventrally. Abdomen without bold 

 black-and-white pattern (rare exceptions). [Forms often with deep median 

 depression in abdominal T5 or with partly metallic head] 



RUTILIA Robineau-Desvoidy (most forms) 

 Intermediate abdominal tergites with discal setae (rarely lacking on one or both 

 tergites but if so then abdomen with black-and-white pattern). Facial carina 

 widest dorsally between junctions of second and third antennal segments and 

 conspicuously narrowed ventrally, not subparallel-sided and not flattened on 

 anterior face. Abdomen most often with bold black-and-white pattern (not 

 in subgenus Paramphibolia). [Forms without wide median depression in 

 abdominal T5 and with the head always non-metallic] . AMPHIBOLIA Macquart 



Key to Australian Subgenera of RUTILIA 



[Note. Occasional specimens may have four postalar setae on one side and three on the 

 other: such specimens should be run as if four setae were present on both sides.] 



1 Parafrontals pollinose, either without metallic colour or only slightly metallic at 



the vertex. Hind tibia either with well developed close-set anterodorsal fringe 

 or with some well developed ad or pd setae or with both fringe and pd setae. 

 Postalar callus with three or more setae ........ 2 



- Parafrontals non-pollinose, entirely brilliant metallic green to blue-violet. Hind 



tibia without anterodorsal fringe and without definite ad or pd setae. Postalar 

 callus with three setae ...... subgenus NEORUTILIA Malloch 



2 Suprasquamal ridge bare and postalar callus with four or five setae. Metallic 



green, blue to purplish black forms with bold white pollen spots on thorax and 

 abdomen ....... subgenus AMENIAMIMA Crosskey 



- Suprasquamal ridge haired, or if bare then only three strong setae on postalar 



callus. Colour and pattern varied, but if bold white pollinose spots present 



then either only three setae on postalar callus or parafacials haired ... 3 



3 Postalar callus with three strong setae. Hind tibia without a definite anterodorsal 



fringe (occasional species with weakly developed or irregular fringe). Two or 

 three sternopleural setae (1 + 1 or 2 -f- 1), anterior stpl conspicuous amongst the 

 sternopleural hair. Hair of suprasquamal ridge rather short and sparse, not 

 noticeably crinkled and never extending on to the lower calypter (ridge bare in a 

 few forms) ............. 4 



- Postalar callus with four or more strong setae. Hind tibia with an anterodorsal 



fringe. One sternopleural seta (o + 1), at most only a very weak anterior stpl 

 seta distinguishable among the hair. Hair of suprasquamal ridge long, dense 

 and bushy, often crinkled and often extending on to basal depression of lower 

 calypter (ridge always haired) ......... 6 



4 Last abdominal tergite (T5) without a median depression, the upper surface evenly 



convex or at most with only a trace of flattening at the tip. Abdominal T3 

 without a transverse row of marginal setae, or if a row present then the setae not 

 markedly spiniform. Scutellum evenly convex on its upper surface. Supra- 

 squamal ridge haired. Arista long-pubescent to short-plumose. Marginal setae 



