TACHINIDAE OF AUSTRALIA 71 



Upper half of face raised medially into a definite ridge-like or knob-like keel beneath 

 the antennae, the keel easily visible when head seen in profile. Abdomen with 

 dense white pollinosity on each side of the last visible tergite (T5), this tergite 

 therefore contrasting in appearance with shining remainder of abdomen. Thoracic 

 dorsum not shining MACROCHLORIA Malloch 



Upper half of face slightly swollen medially but not raised into a keel, face therefore 

 almost completely invisible in profile. Abdomen entirely shining, if some 

 whitish pollinosity present then rather evenly distributed and very inconspicuous. 

 Thoracic dorsum distinctly shining .... CHLOROTACHINA Townsend 



Parafacials bare. Propleuron bare. Wing with cell i? 5 open at the wing margin. 

 Form with remarkable pattern, as follows: dorsum of thorax very pale greyish 

 yellow with six large strongly contrasting black marks (sublateral pair on prescutum 

 and a lateral and a sublateral pair on scutum) ; abdominal dorsum black on 

 Ti -f- 2 and T3 (except for pair of pale greyish yellow marks anteriorly on outer 

 edges of T3) and densely covered with pale greyish yellow pollinosity on T4 and 

 T5, T4 with three bold black spots (median spot and a pair of lateral spots that 

 continue round to ventral surface). Apical half of wing irregularly smoky 

 brownish, the brown colour nowhere sharply contrasting with hyaline areas 



AMPHITROPESA Townsend 



Parafacials haired (Text-fig. 45). Propleuron haired. Wing with cell i? 5 closed at or 

 a little before the margin. Without such pattern, but marked as follows: dorsum 

 of thorax with shining black prescutum and scutum contrasting with yellow or 

 orange scutellum, humeral calli and notopleura, the pale areas with pale golden 

 pollinosity; abdomen bright orange with a broad black fascia across the middle 

 covering T4 and apical part of T3, usually also three small black spots on T5 and 

 median depression of Ti +2 dark. Wing with a sharply defined but irregular 

 brown cross-band, and with the membrane clear hyaline distally to the cross-band 



NEXIMYIA Crosskey 



Tribe PARERIGONINI 



This rare and aberrant group, first defined by Mesnil (1966 : 888), occurs in 

 Eurasia, New Guinea and Australia. Its relationships with other tribes are at present 

 very obscure, but the unusual modification of the male postabdomen, the unusual 

 male genitalia, and the variously modified female terminalia, should shed some 

 light on the true affinities when they are studied in detail. Superficially the New 

 Guinea forms much resemble some Goniinae, and Australian forms like Zita have 

 a general appearance, head facies and scutellar bristling much like some Proseninae; 

 there is also some superficial resemblance to the Linnacmyini, mainly because of 

 the prominent epistome and high vibrissae, and Pygidimyia has the colour and 

 form much as in Chaetophthalrmis . The Australian genera are known only from 

 very few specimens, but these include representatives of some new species. 



The main characteristics shown by the Australian Parerigonini are as follows. Epistome 

 prominent and vibrissae inserted high above the epistomal margin; parafacials bare; genal 

 dilation well developed; $ without proclinate orbital setae, 9 with a pair of outwardly directed 

 prevertical setae; inner vertical setae often convergent or crossing; upper occiput without 

 black setulae behind the postocular row; prosternum bare; propleuron usually haired; humeral 

 callus with three strong setae in a triangle, and one smaller seta set forwards of the inner two 

 of the triangle; 3 (4) + 3 dc setae; o + 2 ia setae (the two post ia setae very strong and 

 normally inserted in a position that suggests that a third post ia is never developed) ; three 



