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 en Ale bare area from haired 
genal dilations : i : 2 : ; 6 
6 Intermediate abdominal tergites achout 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 Pavamphibolia). [Forms without wide median depression in 
abdominal T5 and with the head always non-metallic] . AMPHIBOLIA Macquart 
Kry 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 sii setae. 
Postalar callus with three or more setae . : : 2 
— Parafrontals non-pollinose, entirely brilliant rmetalllios reo to cen 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 poetalen 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 ieee or = pa hed 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 aritercdomsedl 
fringe (occasional species with weakly developed or irregular fringe). Two or 
three sternopleural setae (I + 1 or 2 + 1), anterior stp/ conspicuous amongst the 
sternopleural hair. Hair of suprasquamal ridge rather short and sparse, not 
noticeably crinkled and never ee on to the lower calypter (ridge bare in a 
few forms) . : : : : P 3 4 
— Postalar callus ae fours or more sbroue setae. Hind tibia with an anterodorsal 
fringe. One sternopleural seta (o + I), at most only a very weak anterior stp/l 
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 ou depression, cee Fare eaciaee ee 
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 
