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UNITED STATES NATIONAL MUSEUM BULLETIN 224 



the face, and epistomal bristles in a transverse row 

 which may consist of only 1 or 2 pairs and a few ad- 

 ditional fine, slender hairs; at least 1 pair is curved, 

 stout and long, and directed obliquely forward and 

 downward. The front is polished and bare, except for 

 a narrow band of pubescence along the eye margin and 

 has 3 or 4 fine, short hairs laterally. Vertex moderately 

 excavated, the ocellar protuberance rather large with 

 steep, slanting sides and only 2 or 3 fine, short hairs 

 posteriorly behind the ocelli. Eye facets enlarged 

 centrally. 



Thorax : The thorax is everywhere appressed micro- 

 pubescent. Pile of mesonotum is very scanty, fine and 

 setate, acrostical elements absent, dorsocentral bristles 

 or hairs present, becoming a little longer and stouter 

 posteriorly. Humerus with a few, fine hairs. The 

 lateral bristles are long and stout and consist of 1 

 notopleural, 1 supraalar, 1 postalar, and no scutellar 

 bristles. Scutellum flat, wrinkled, pubescent and api- 

 lose. Anterior ventral propleuron with 10 to 12 fine, 

 long hairs. The pronotum has 4 or 5 fine hairs on each 

 side. Upper mesopleuron with 5 or 6 fine, short hairs, 3 

 or 4 on the posterior hypopleuron ; pteropleuron and 

 sternopleuron apilose. Metapleuron with 6 or 7 very 

 slender, long, bristly hairs. Metanotal slopes micro- 

 pubescent only. Lateral metastemum polished, with 

 some pile; ventral metastemum chitinized, without 

 pile; postmetacoxal area membranous; tegul a pubescent 

 only. Presternum quite small and dissociated. 



Legs: All the femora are elongate, the middle pair 

 slightly dilated distally. The pile of the legs is very 

 short, scanty and appressed. The bristles present con- 

 sist of 2 laterally near the base of the hind femur, 2 

 medially before the middle, 2 rather stout, long bristles 

 medially at the apex and 1 dorsally at the apex. Hind 

 tibia with 5 stout, moderately long dorsal bristles, the 

 first of them doubled and with 4 lateral and a single 

 ventral bristle near the apex. Ventral surface of this 

 tibia with numerous, rather longer, oblique setae. A 

 brush of setae present on the distal half begins at the 

 basal third and becomes ranked into conspicuous, 

 straight, transverse rows that appear like scales in some 

 lights. Middle femur with 5 lateral bristles on the basal 

 half and 3 medial and a long, stout, subapical basal 

 bristle laterally, dorsally and medially. Middle tibia 

 with 5 dorsomedial, 5 dorsolateral, and 2 ventral bristles 

 confined to the outer half. The apical circlet has 10 

 bristles. Anterior femur with 2 bristles at the apex 

 dorsally and posteriorly. Its tibia with 5 dorsal, 5 

 posterior, 1 very long ventral, and 1 equally long, sub- 

 apical, anterior bristle. A brush of setae begins at the 

 basal third. Apex of anterior tibia with a strong, 

 basally swollen, elongate spine. Basitarsus with a tri- 

 angular plate. The anterior basitarsus and succeeding 

 segments ventrally have a dense, short, erect fringe of 

 fine pile on the ventrolateral half, replaced by appressed 

 setae on the opposite half. All tarsi end in sharp claws, 

 long pulvilli, and empodia. 



Wings: The marginal cell is widely open; anterior 

 branch of the third vein ends at wing apex, the posterior 



branch well behind it ; first posterior cell widely open, 

 fourth closed and stalked; anal cell closed and stalked. 

 Alula short; second basal cell ends in 3 veins; ambient 

 vein complete. The wing is subhyaline with glassy 

 appearance; everywhere microvillose. 



Abdomen : The abdomen is elongate and subclavate, 

 the first 2 or 3 tergites in lateral profile are corrugate, 

 or bullose posteriorly and depressed anteriorly. Males 

 with seven tergites, the seventh at least three-fourths 

 as long as the sixth. There may be a lateral trace or 

 lip of the eighth tergite exposed. Females with eight 

 tergites, the eighth nearly as long as the second. Pile 

 of abdomen very sparse, fine and suberect, leaving the 

 abdomen almost bare and shining. Sides of the first 

 tergite with 1 or 2 short bristles. Abdomen approxi- 

 mately as long as the wings. Male terminalia rotate 

 and dominated by the uncleft, unnotched epandrium 

 which together with the semi fused, thinned proctiger 

 forms a hemicylindroid sleeve or collar; the apical 

 proctiger has a small dorsal, inwardly curled process 

 which meets the opposite process ; and below a longer, 

 more triangular, thin process which is only a little 

 curved inward. Gonopod moderate in size, with a long, 

 slender, flat process and an interior, shorter, toothed 

 process. Hypandrium distinctly narrow but moder- 

 ately long. 



Distribution : Neotropical : Mirolestes aTbimanus Car- 

 rera (1949) ; barbiellinii Curran (1935) ; facialis Cur- 

 ran (1935) ; lynchii Brethes (1904) [ = pleuralis Cur- 

 ran (1935)]. 



Genus Neolaparus Williston 



Figures 520, 573, 1090, 1099, 1768, 1991, 2013 



Laparus Loew, Bemerkungen iiber die Faniilie Asiliden, p. 4, 



1851. Preoccupied Lepidoptera, 1820. Type of genus : 



Laparus tabidus Loew, 1851, by monotypy. 

 Neolaparus Williston, Psyche, vol. 5, p. 255, 1889, change of 



name. 

 Cenopogon Wulp, Tidjschr. Ent, vol. 41, p. 120, 1898. Type of 



genus: Dasypogon volcatus Walker, 1849, as Cenopogon 



bifidus Wulp, 1898, by monotypy. 



Flies of medium size with quite slender, slightly 

 clavate abdomen, slender, elongate legs, elongate neck 

 and with short, reduced pile. On the face the bristles 

 are restricted to 1 row along the epistomal margin, and 

 in some instances reduced to 1 pair. Anterior basi- 

 tarsus with a single flange. Probably the nearest New 

 World related genus is Mirolestes Curran with closed 

 and stalked fourth posterior cell and different male 

 terminalia. Length 15 mm. 



Head, lateral aspect: The head is comparatively 

 long. The face is prominent throughout but especially 

 so on the lower portion where it is comparatively pro- 

 tuberant. The eye is strongly recessive antero ven- 

 trally. Both anterior and posterior profiles are 

 strongly convex. The occiput is obliterated from the 

 middle of the head but prominent below and more 

 swollen medially. Pile is abundant, long and fine, with 

 only 2 bristles, these located behind the vertex and 



