ROBBER FLIES OF THE WORLD 



565 



femora and the anterior tibia and still more conspicu- 

 ously on the comparatively short, robust and slightly 

 compressed abdomen. The second to fifth tergites are 

 especially well covered with long, rather coarse, matted 

 pile. Length 20 mm. 



Head, lateral aspect : The head is rather longer than 

 in Machimus; the gibbosity of the face is large and 

 prominent leaving the upper fourth shorter, rather 

 more prominent than in Machimus. The occiput is well 

 developed, especially on the lower tliird; the eye is 

 strongly recessive posteroventrally. Pile of lower oc- 

 ciput remarkably long, fine, dense and tufted. The 

 upper occiput behind the eye has 6 pairs of stout 

 bristles and 7 or 8 pairs of weak bristles still lower on 

 the head. The proboscis is comparatively short and 

 quite robust, bluntly pointed. Antemia attached a little 

 above the middle of the head, the first two segments 

 with numerous, slender, bristly hairs. Third segment 

 similar to Machimus. 



Head, anterior aspect: The face below the antexma 

 is less tlian a fifth the head width and strongly diver- 

 gent below; it is pubescent, witliout pile on the short, 

 dorsal portion; the gibbosity bears quite numerous, 

 long, slender bristles, which are continued down on the 

 cheeks. The front is short, pollinose, divergent, with a 

 wide, undifferentiated band of quite long, slender 

 bristles or bristly hairs on each lateral third; the medial 

 third of the front is sunken. The vertex is narrowed 

 and moderately excavated ; the ocellarium is imusually 

 large and low, with between the ocelli, lateral patches 

 of about 12 long, slender, bristly hairs and other hairs 

 behind the ocelli. 



Thorax : The mesonotum has numerous, long, bristly 

 setae, nearly erect ; acrostical elements are undifferenti- 

 ated; there are dorsocentral bristles only on the pos- 

 terior half but all of them are slender. Posterior 

 fourth of mesonotum with a broad band of numerous, 

 long, bristly hairs. The lateral bristles are stout and 

 consist of 2 notopleural, 2 supraalar, 2 postsupraalar, 

 3 or 4 postalar and equally long, bristly pile. Scutellar 

 margin with 8 to 10 pairs of long, slender bristles in 

 each of 2 rows and additional, equally long, stiff pile 

 \ on the disc. All tufts of pleural pile more dense, often 

 longer than in Machimus. Metanotal callosity excep- 

 tionally bullose with dense, bristly pile. Postmeta- 

 ' coxal area membranous. The metastemum is densely 

 ' long pilose. 



Legs : The legs are similar to Machimus; the femora 



have few bristles but more extensive, long, stiff hairs 



continued on to the tibiae, especially the first four pairs. 



The tibial bristles are numerous and quite stout, more 



or less reduced on the first pair. Hmd femur with 7 



[« ventrolateral bristles near the apex. The hind tibia has 



' 10 stout, dorsolateral bristles, 4 ventrolateral and 4 



ventromedial bristles. Claws sharp, bent apically, the 



61 pulvilli and empodium long. 



in Wings: The wings are similar to Machimus-^ second 



or submarginal cell is widened both above and below its 

 lie origin and a little constricted near the middle. The 



first posterior cell is considerably narrowed in the 

 middle because of the second submarginal cell. 



Abdomen: The abdomen is shorter and more robust 

 than in Machimus and densely pilose on the second to 

 fifth tergites. Terminalia similar. 



Distribution: Palaearctic: TrichomMchimus excelsus 

 Kicardo (1922) ; p-w&escerw Ricardo (1922). 



Genus Eutolmus Loew 

 Figures 365, 771, 1509, 1518, 2320, 2347, 2385, 2388 



Eutolmus Loew, Linnaea Entomologica, vol. 3, p. 459, 1848. 

 Type of genus : AsiJus ruflharbis Meigen, 1820, in Engel, 

 1928, by original designation. 



Medium size flies related to Machimus Loew. The 

 face has a rather prominent gibbosity with numerous, 

 long bristles. Dorsocentral bristles on the thorax are 

 confined to the posterior half; the scutellar margin 

 bears several pairs of bristles, but in contrast, the disc 

 usually has only a few, fine, scanty hairs. Metanotal 

 callosity bullose and bristly. The aedeagus has three 

 prongs; the eighth sternite of the male has a rather 

 long, excised process at the apex. The females resemble 

 Dysmachus Loew by likewise possessing a remarkably 

 compressed ovipositor with wedged-in proctiger and I 

 believe their true relationship is with this genus. 

 Length 12 to 20 mm. 



Head, lateral aspect : The head is comparatively long 

 and tlie face prominent with a rather strong gibbosity, 

 densely covered with bristles, some fine and some stout. 

 The upper third of the face or less is nearly plane with 

 the eye and bears micropubescence only. The occiput is 

 moderately prominent throughout and not more promi- 

 nent below even though the ventral fourth of the eye is 

 strongly and angularly recessive. Lower occipital pile 

 dense and fine; upper pile with slender bristles and in 

 addition some 5 pairs of more stout bristles situated 

 behind the upper eye corners. These bristles are 

 slightly curved. The proboscis is comparatively weak 

 and cylindrical and a little swollen at the base; it is 

 bluntly pointed with short, apical bristles and it is 

 barely extended beyond the face ; it is thrust obliquely 

 forward. The palpus is of only medium size ; it is ex- 

 cavated on the basal half and bears weak, apical bristles ; 

 there appears to be a trace of the basal segment. An- 

 tenna attached a little below the upper third of the 

 head, elongate, as long as the head; the first two seg- 

 ments are rather long and slender, the second segment 

 shorter. The third segment is as long as the combined 

 length of the first two segments ; it has a short, distinct 

 microsegment, comparatively short, stout style, no 

 longer than the tliird segment and bears a bristle at tip. 



Head, anterior aspect : The face below antenna a sixth 

 the head width, and strongly divergent below; it is 

 micropubescent and pile generally is confined to the 

 lower side of the concave, oblique, subepistomal area. 

 Bristles of face are numerous, usually more slender on 

 the upper half of the gibbosity, stout below and con- 

 tinued down the sides of the subepistoma. The front 



