
| 

| 
TACHINIDAE OF AUSTRALIA 93 
times absent) and directed at least slightly upwards, if strong and horizontal 
then weaker than subapical scutellar setae. ‘ é . : ‘ 3 
Eyes haired (hairing long, dense and very conspicuous) : : 4 
Eyes bare (a few very minute hairs sometimes visible under high Raamnertien : 13 
Head without definite reclinate orbital setae. Frontal region bulbously convex 
and with very reduced frontal setae (fig. 21 in Malloch, 1929b). Head ground 
colour bright orange-yellow with blackish ocellar triangle. Legs unicolorous 
orange-yellow. Abdomen thickly greyish white pollinose with a pattern of 
black spots. Each side of venter of abdominal tergites 3 and 4 in g with a 
dense hair fascicle - : ARRHENOMYZA Malloch 
Head with one or more pairs of strong reclinate orbital setae. Frontal region not 
bulbously convex (distinctly flattened when seen in profile) and with well developed 
frontal setae. Head ground colour not so. Legs black or brownish black 
(except in Zebromyia). Abdomen without such pattern. g without dense hair 
fascicles on abdominal venter - 5 
Facial ridges very wide and covered with several irregular rows of small strong 
setulae (setulae only slightly increasing in size towards front edge of ridge). 
Parafacials haired at upper ends immediately below lowest frontal setae. 
Prescutum and scutum each with a transverse row of four small black spots 
anteriorly (distinct against the yellowish grey pollinose background). Abdomen 
conspicuously patterned, T3—-T5 greyish yellow pollinose with dark marks in 
form of a pair of wide blackish or dark reddish brown triangles on T3 and T4 
and a pair of small round black spots at tip of T5. Head with reddish ground 
colour and chequered silvery white aan that appears to shift with direction 
of light. Legs reddish yellow : : ZEBROMYIA Malloch 
Facial ridges bare or setose; if setose then with ; a row ‘of strong setae on front edge 
and only one or two inconspicuous setulae outside of the main row. Parafacials 
either completely haired or completely bare. Prescutum and scutum without 
such pattern. Abdomen without such pattern. Head not so. Legs black 
or brownish black : - ‘ : : : : 6 
Parafacials completely haired. Ocellar setae absent. Always fewer than four 
sternopleuralsetae. Lateral scutellar setae absent (except in occasional specimens 
of Polychaeta) : : 4 é : : 3 i ; : : 
Parafacials bare. Ocellar setae present or absent. Sometimes four s¢p/ setae. 
Lateral scutellar setae present ; 9 
Dorsum of abdomen shining black or eee dane red-brown eecepe for last cavibl 
tergite (T5) which is thickly coated with uniform whitish pollinosity (pale last 
abdominal segment therefore strikingly contrasting with the rest of the abdomen) 
EURYGASTROPSIS Townsend 
Abdomen not so, ground colour reddish to blackish with thin whitish pollinosity 
(sometimes appearing patchily distributed) on all tergites, no segments shining 
and last segment not contrasted in colour with remainder of abdomen. : 8 
Arista thickened on more than its basal half, sometimes on most of its length: 
second aristal segment normally at least 2-5 times as long as broad. Pollinosity 
of abdomen tending, to naked eye, to appear more conspicuous anteriorly on 
segments than elsewhere or to appear rather chequered. Smaller forms, length 
8-IImm . ‘ TRITAXYS Macquart 
Arista only thickened on ts basal half or less: second aristal segment not more 
than twice as long as broad. Pollinosity of abdomen tending, to naked eye, 
to appear as a very thin but evenly distributed bloom. Larger forms, length 
I2-16mm . POLYCHAETA Macquart 
[This genus is only — doubttally deans on Tritaxys] 
Four sternopleural setae (2 + 2). Second aristal segment distinctly elongate 
(about three times as long as broad or more) : : = : : : 10 
“I 
