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UNITED STATES NATIONAL MUSEUM BULLETIN 224 



Genus Habropogon Loew 



Figubes 134, 513, 1109, 1118, 1752, 1756, 1777, 1828 



Habropogon Loew, Linnaea Entomologiea, vol. 2, p. 463, 1847. 

 Type of genus: Dasypogon exquisitus Meigen, 1820. Desig- 

 nated by Coquillett, 1910, the first of two species. 



Dactiliscus Itondani, Dipterologiae Italica prodromus, vol. 1, 

 p. 158, 1856. Type of genus: Asilus striatus Fabricius, 

 1794, by original designation. 



Dactyliscus Marschall, Nomenclator Zoologicus, p. 327, 1873. 

 Lapsus. 



Small to medium size flies for the most part with 

 short or reduced pile and strongly pollinose. The vertex 

 shows little or no excavation, the lower half of the face 

 lias a dense mystax of slender bristles or bristly hair. 

 The palpus is large, the second segment especially large 

 and swollen with dense, bristly pile. The medial sur- 

 face flattened, smooth and bare. Length 9 to 14 mm. 



Head, lateral aspect: The face is rather short, gently 

 convex, either receding below or sometimes nearly 

 straight on the upper portion. The eye is unusually 

 long, strongly convex anteriorly, gently convex behind. 

 The occiput is exceptionally prominent and very thick 

 and continues in that extent to the vertex; the pile is 

 moderately dense, stiff and coarse ventrally and is re- 

 placed by a wide band of numerous, deeply submarginal 

 bristles dorsally. In some species these dorsal bristles 

 are rather longer, more slender, strongly curled for- 

 ward. The proboscis is moderately long, stout, concave 

 below, and dorsovent rally compressed on the apical 

 third; from a lateral aspect the base is swollen ven- 

 trally and it has a prominent, high medial ridge ex- 

 tending to the outer third. The apex bears a few short, 

 fine hairs, the base some longer stiff pile below. Palpus 

 with the basal segment short and membranous laterally, 

 chitinized below, fused medially; the second segment 

 characteristically is unusually large, swollen, and car- 

 ries numerous, long, stiff hairs or bristly pile except 

 that the dorsomedial surface is more or less flattened 

 and apilose. 



Head, anterior aspect : The face below antenna is 

 about one- fourth the head width and divergent below; 

 the front is slightly divergent above at the vertex. 

 Subepistomal area moderately large but only slightly 

 oblique, deeply concave with a high, thin, medial ridge. 

 The face is pubescent on the lower half or two-thirds 

 and bears dense, slender, bristly pile or weak bristles; 

 in some species these elements are so dense as to form 

 a rooflike enclosure over the epistomal area, much as in 

 Stichopogon Loew. The antenna is attached at or 

 above the upper third of the head, only moderately 

 elongate, the first two segments short, of nearly equal 

 length, or the first segment a little longer than the 

 second. The third segment is somewhat widened in the 

 middle, gently tapered towards the base and apex; 

 it bears a single elongate and slender microsegment 5 

 or 6 times as long as wide, truncate apically, with a 

 minute spine. The pile of the first and second segments 

 consists of several stiff, short, bristly hairs ventrally 

 with sometimes 2 elements accentuated on the first seg- 



ment and one long stiff bristle ventrally on the second 

 segment. Dorsal bristles at the apex of the second seg- 

 ment usually short but in some species long and stout. 

 The front is short and pollinose with a single ocular row 

 of slender or stout bristles, 6 or 7 in number. Vertex 

 but little excavated, the ocellarium large but low with 

 vertical sides and bearing either 2 or 3 short bristles be- 

 tween the ocelli or 2 or 3 pairs of long, slender bristles 

 with several additional bristles behind the posterior 

 ocelli. The front varies in width; it may be rather 

 strongly divergent, the vertex not at all excavated or 

 the front may be very slightly wider in the middle than 

 at the antenna, convergent again at the vertex. Central 

 eye facets moderately enlarged. 



Thorax: The thorax is strongly pollinose, the pile 

 of the mesonotum is abundant, more or less erect, 

 stiff and bristly, rather fine laterally. There are 

 no humeral, acrostical, or dorsocentral elements dif- 

 ferentiated anteriorly, the latter may, on the posterior 

 half of the mesonotum, develop into a longitudinal 

 row of 4 or 5 long, medium stout bristles, or the whole 

 posterior half of the mesonotum may be covered with 

 quite long, slender bristles. The following comple- 

 ment of lateral bristles may be present: 2 to 5 noto- 

 pleural, 5 to 11 supraalar, 3 or 4 postalar, and 7 or 

 8 pairs on the scutellum. Scutellum flat, pollinose, 

 without pile. Propleuron with abundant, long, stiff 

 pile ventrally on the anterior collar and especially on 

 the dorsal postpropleuron ; bristles usually absent, but 

 are occasionally present. Upper mesopleuron and 

 anterior sternopleuron with pile; there may be weak 

 bristles narrowly along the dorsal margin of the meso- 

 pleuron. The posterior sternopleuron, pteropleuron, 

 and hypopleuron apilose. Metapleuron with a vertical 

 band of numerous, stout bristles and more slender hair 

 intermixed. Metanotal slopes micropubescent only; 

 tegula with bristles; anterior basalare characteris- 

 tically with a conspicuous tuft of long, abundant, 

 bristly pile. Lateral metasternum posteriorly with 

 pile, ventral metasternum wide, chitinized, densely long 

 pilose, isolated behind; the postmetacoxal area mem- 

 branous. Prosternum dissociated. 



Legs: The legs are stout without being swollen; 

 densely covered with long, flat appressed, coarse pile 

 on the dorsal and lateral surfaces of the femora, be- 

 coming more erect on the ventral half; the tibiae 

 are covered with similar, appressed or subappressed, 

 abundant pile, the bristles rather prominent. The fol- 

 lowing complement of bristles may be present: the 

 hind femur with 8 lateral and with a row or cluster 

 dorsolaterally near the apex of 3 to 7 bristles; the im- 

 mediate apex may have 3 dorsolaterally and 3 medially 

 in addition to the others named. Ventral surface with 

 10 to 12 long, slender hairs, absent in some species. 

 Hind tibia with 5 or 6 slender, dorsal bristles. Lateral 

 elements consist of 2 well developed bristles on the 

 outer half, 1 or 2 very slender, long hairs basolaterally. 

 There may be present a second dorsolateral row con- 

 sisting of 5 very short or even long and short bristles. 

 Middle femur with numerous bristles on the apical 



