TACHINIDAE OF AUSTRALIA 43 



haired along its length (except in Chetogaster in which hind part bare). Head 

 always with a strong facial carina. Scutellum with four or more pairs of marginal 

 setae (except in Chetogaster with three). Male hypopygium with long strong 

 erect setae on T7 + 8 (usually standing in line on each side of the tergite). 

 Prosternal membrane bare or haired, presternum bare except in some forms with 

 haired prosternal membrane ....... RUTILIINI (p. 47) 



Tribe PROSENINI 



This tribe contains the great bulk of members of the subfamily Proseninae when 

 the whole world fauna is considered, but in Australia (even allowing that there 

 are doubtless many undescribed forms) forms only a minor proportion of the total 

 prosenine fauna - most of the Australian fauna being comprised by the Rutiliini. 

 The features that differentiate the Prosenini from the Rutiliini are shown in the 

 foregoing key to tribes, and the characteristics of the Prosenini need not be detailed 

 here (further information is, however, given in Crosskey, 1973). The Australian 

 Prosenini fall into two main groups, one containing forms with a heavy broad 

 facial carina that fully separates the antennae and with reduced palpi, and another 

 group (somewhat diverse in its components) containing forms without a facial 

 carina, or with a sharp median facial ridge, and with fully developed palpi. 



The first of these groups contains the widespread Old World genus Prosena 

 in which the proboscis is enormously elongate and slender, and a complex of forms 

 closely related to Prosena in which the proboscis is much shorter and stiffer. Several 

 genera have been proposed among the latter forms (Senostoma, Rhynchiodexia, 

 Austrodexia, Macropodexia, Lasiocalypter, Lasiocalytrina) but these merge so 

 imperceptibly into one another - with few character breaks that are maintained 

 when sufficient material is examined of the complex - that it is impossible to 

 recognize most of them as valid genera. The oldest name applying to the complex 

 of forms with short proboscis, strong facial carina, and reduced palpi is Senostoma 

 Macquart (a name misused for many years and erroneously applied to various 

 rutiliines) and all the other names, except Macropodexia, are here placed as synonyms 

 of Senostoma ; the broad genus so recognized can be identified by the accompanying 

 key to genera. The genus Macropodexia is superficially hardly distinguishable 

 from many of the species of Senostoma, but it has the propleuron thickly pale 

 haired and so differs from all Senostoma s.l. and from Prosena; probably Macropodexia 

 ought also to be placed as a synonym of Senostoma and the definition of the genus 

 widened, but it is here preferred to retain Macropodexia as valid until the whole 

 complex can be studied in more detail by an Australian worker with more material 

 to hand. It is of interest to note that the propleural hair is white in Macropodexia 

 whereas it is black in all other known Australian Prosenini with haired propleuron. 



The second group contains a number of endemic Australian genera that differ 

 from the first group {Prosena, Senostoma complex) in having fully developed palpi 

 and in the conformation of the facial region of the head (either lacking a facial 

 carina or having a sharp ridge-like keel) . The forms in this second group are rather 

 diversified. Most of them form an apparently natural complex in which the 



