DASVPOGONINAE 



ROBBER FLIES OF THE WORLD 



293 



epandrium cleft and apposed; female with acantho- 

 phorites and spines. Presternum dissociated. Length 

 12 to 16 mm. 



Head, lateral aspect : The face is quite short, almost 

 plane with the eye except at the epistoma, which is very 

 slightly produced. Occiput prominent, especially on 

 the lower third, which bears dense, moderately long, 

 whitish pile. At the middle of the head there are weak, 

 white bristles replaced above by numerous, stout, white 

 bristles situated in 1 row and a patch of similar bristles 

 behind the vertex, 17 on each side. Proboscis short 

 but extending beyond the face, plane below, arched 

 above towards the apex and with a dorsal ridge or keel. 

 The apex has fine pile and the base bears a few, long 

 hairs below. Palpus of two segments, the first appar- 

 ently cylindrical, the second also cylindrical, longer, and 

 with rather numerous, fine to coarse hairs. The an- 

 tenna is attached a little below the upper third of the 

 head and approximately as long as the head. First 

 two segments equal in length, each iy 2 times as long as 

 high, and the third not quite twice the combined length 

 of the first two. The third segment at base is less wide 

 than the second, through the middle it is a little widened 

 and close to the apex tapered and narrowed, ending in 

 a small, transverse opening with minute, exposed spine. 

 First segment with several weak bristles ventrally and 

 laterally and setae above; second segment similar but 

 with shorter bristles. 



Head, anterior aspect : The head is twice as wide as 

 high, the face is approximately one-fourth the head 

 width and barely wider below. The cheeks scarcely 

 extend below the eye. While the face is not high, the 

 subepistoma is not large either. Face without pile, 

 densely pale micropubescent with 2 or 3 rows of close- 

 set, rather long, stout, whitish bristles placed trans- 

 versely above the epistoma and extending beyond the 

 proboscis. The lower face contains approximately 36 

 bristles. Front considerably wider than upper face 

 and the vertex is barely narrowed. The front is rather 

 long, more or less flattened but near the eye margin 

 sunken and sloping downward. Ocular margin with 

 a row of fine bristles and an additional band of bristles 

 submedially on the front. Ocellarium moderately 

 large, low, with large ocelli and 3 pairs of long, stout 

 bristles, and sometimes 1 or 2 additional setae. 



Thorax : The mesonotum is moderately high, abrupt 

 anteriorly, everywhere pollinose with a wide, bare, 

 medial band containing an acrostical row of stout setae. 

 Dorsocentral setae or short bristles are well developed 

 in the middle and behind the suture consist of 4 long, 

 prominent bristles. Lateral bristles are stout and long 

 and consist of 2 anterior humeral, 2 notopleural, 2 

 supraalar, 2 on the postalar callosity, and 1 pair on the 

 scutellum which are crossed. Scutellum flat on the disc 

 and pollinose only. Metanotal callosity prominent and 

 pollinose only. Pleuron densely pale pollinose without 

 pile except on the propleuron where there is also later- 



ally a stout bristle. Pronotal bristles weak; the meta- 

 pleuron has a vertical row of 8 bristles and some other 

 long hairs. Postmetacoxal area membranous; lateral 

 metasternum pilose; ventral metasternum with only 1 

 or 2 hairs ; presternum fully dissociated. 



Legs : The legs are not of unusual length and every- 

 where comparatively slender with abundant, appressed, 

 fine setae and comparatively few bristles, and almost 

 none on the femora. Hind femur with 1 lateral bristle 

 near the base; middle femur with 1 bristle postero- 

 dorsally near the apex; anterior femur with none. 

 Posterior tibia with 4 dorsolateral bristles, 3 of them 

 on the basal half, 2 longer, stouter dorsomedial bristles, 

 1 on each half, besides 2 other shorter basal elements ; 

 this tibia also with 3 ventrolateral bristles, the apex with 

 7 bristles. The slender basitarsus is as long as the next 

 three segments. Middle tibia with four short and 1 

 long distal anterodorsal bristle and 4 short, postero- 

 dorsal bristles, besides 4 posteroventral and 1 conspic- 

 uous distal ventral bristle. Anterior femur with 5 

 anterodorsal, 4 posterodorsal, and 2 conspicuous, long, 

 posteroventral bristles. Apex with a medial or medio- 

 ventral, twisted, curved spine resting against a patch 

 of minute, black denticles on the basitarsus. All tarsi 

 end in long, slender, sharp claws bent at the apex, well 

 developed pulvilli and long, bladelike empodium. 



Wings : The wings are hyaline and slender, the mar- 

 ginal cell closed with a short stalk, the first posterior 

 cell is rather widely open though a little narrowed. 

 Fourth posterior cell greatly narrowed, possibly some- 

 times closed. Anal cell closed in the margin or nar- 

 rowly open. Alula large, ambient vein complete, wing 

 densely covered with quite minute villi. 



Abdomen: The abdomen, like the thorax, is dark 

 brown, with dense, pale pollen, changing appearance 

 with the direction of light. Postmargin yellowish. 

 The first segment is as wide as the mesonotum and 

 beyond the abdomen is rather strongly tapered and is 

 cylindrical distally. It is thinly covered with small, 

 appressed, pale setae. Sides of the first segment with 

 some longer pile and 6 slender, pale bristles. Males 

 with eight segments, the eighth only half as long as 

 the seventh which is shorter than the sixth. Females 

 with eight segments, the eighth more than half as long 

 as the long seventh segment. Male terminalia moder- 

 ately large, usually rotate about one-fourth, broad but 

 somewhat depressed ; the epandrium is large, fully cleft 

 but with tightly apposed sides and the proctiger extends 

 beyond. Hypandrium large, gonopod moderately 

 large, convex laterally with apical process bent down- 

 ward. Genital cavity fully exposed. Whole termi- 

 nalia with numerous, fine, long hairs and quite slender 

 bristles. Female terminalia with acanthophorites and 

 5 pairs of moderately sharp spines. 



Distribution : Australian : Metalaphria aurifacies 

 White (1917); australis Ricardo (1912); tessellata 

 Hardy (1930). 



