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UNITED STATES NATIONAL MUSEUM BULLETIN 2 24 



bears 3 sets in a straight row, the supraalar region 1, 

 the postalar callosity 1 bristle. Scutellura rather flat, 

 thin, pollinose, without pile and without basal crease 

 except for minute pockets laterally. Metanotal cal- 

 losity bullose, pollinose only. Pleuron pale pollinose 

 with almost no pile even on the propleuron. The 

 pronotum, however, bears a conspicuous row of 4 pairs 

 of long, regularly spaced, medium stout bristles and 

 the lateral propleuron has a still longer, spikelike 

 bristle. Humerus with setae only. Metapleuron with 

 an oblique row of 3 medium stout bristles, 3 more 

 slender, and anterior to this row 2 or 3 hairs. Post- 

 metacoxal area membranous; the lateral metasternum 

 bears pile; the ventral metasternum pollinose only; 

 prosternum dissociated. 



Legs: The legs are comparatively elongate, especi- 

 ally the hind pair. The hind femur is slender at the 

 base, swollen distally above and below, and all the 

 legs bear scattered, fine, appressed setae, mostly want- 

 ing on the lower surfaces and quite scanty on the tibia. 

 The hind femur has 4 short, moderately stout bristles 

 ending at the point of greatest swelling; also 7 quite 

 short, stout, ventrolateral bristles; no bristles are at 

 apex. The very slender, elongate tibia, swollen only 

 quite close to the apex, bears short bristles only. It has 

 4 regularly spaced dorsolateral, 1 basal, 1 dorsomedial, 

 1 at the middle, and 2 beyond. It also has 5 ventro- 

 lateral bristles of which the last 2 are little longer and 

 stouter. Medially there are dense setae only close to 

 the apex, and the apex has 1 lateral and 4 ventral 

 bristles. All the basitarsi are long and slender. 

 Middle femur with 2 quite small posterior or postero- 

 dorsal bristles on the apical fourth, 1 posteroventral 

 bristle, 4 even shorter anteroventral bristles. This 

 tibia bears very short bristles, consisting of 3 postero- 

 dorsal, 3 anterodorsol, 3 or 4 posteroventral, 4 antero- 

 ventral, the last element longer, and 2 longer, stouter, 

 distal ventral bristles, besides 3 long, stout ventral, 

 apical bristles, and 2 weak, dorsal apical, bristly hairs. 

 Anterior legs missing. Claws moderately stout, sharp, 

 rectangularly bent at apex ; the pulvillus long ; the em- 

 podium small, long and bladelike. 



Wings : The wings are long, narrowed distally and 

 rather darkly tinged with brown. The marginal cell 

 is widely open, the second submarginal cell is narrow, 

 at base nearly equally divided above and below the 

 third vein. The upper branch of the third vein ends 

 at the wing apex. The posterior branch ends behind 

 the apex at a point not quite equal the ending of the 

 second vein. Marginal cells maximally open except 

 the fourth, which is narrowed to less than half its 

 maximal width. Anal cell open. Alula twice as wide 

 as the costal cell, ambient vein complete. Posterior 

 crossvein almost eliminated, the upper anterior inter- 

 calary vein short, the anterior crossvein rectangular, 

 entering the discal cell a little beyond the middle, the 

 third vein forks beyond the end of the discal cell. 



Abdomen: The abdomen is comparatively robust 

 with nearly parallel sides but the first and fifth tergites 

 are slightly wider. The surface is pollinose with scat- 



tered, appressed, stout setae and no long pile laterally 

 except anteriorly on the sides of the first segment. The 

 first segment is rather long, bears laterally on its pos- 

 terior margin 3 stout, pale bristles. Sides of the fifth 

 and sixth segments sublaterally with a large patch of 

 appressed, dark reddish clavate bristles. Basal fourth 

 of second segment with a prominent, shallow, trans- 

 verse fossa. Males with seven tergites, the seventh less 

 than half as long as the sixth and shorter laterally. 

 The sixth is a little more than half as long as the fifth. 

 Male terminalia large, rather high, completely rotate so 

 that the long, wholly cleft, superior forceps, each half 

 of which is subcylindrical and apically pointed, hangs 

 downward like a bowl with a large, short proctiger in 

 between. The gonopod is large, or larger than the 

 forceps, strongly swollen or convex laterally, with a 

 long, dorsomedial, posteriorly toothed process ; it bears 

 posteriorly and ventrally several slender bristles and 

 bristly hairs. Hypandrium large and half as long as 

 the forceps. 



Distribution: Neotropical: Cleptomyia baclllifera 

 Carrera (1949). 



Genus Theromyia Williston 



Figures 170, 1142, 1151, 1874, 1908 



Cylindrophora Philippi, Verb, zool.-bot. Ges. Wien, vol. 15, p. 



704, 1865. Preoccupied Coleoptera, 1851. Type of genus: 



Cylindrophora murina Philippi, 1865, by monotypy. 

 Lynchia Williston, Psyche, vol. 5, p. 255, 1889. Preoccupied 



Diptera, 1882. 

 Myiothcra Williston, Psyche, vol. 5, p. 259, 1889. Preoccupied 



Aves, 1811. 

 Theromyia Williston, Trans. American Bnt. Soc, vol. 18, p. 73, 



1891. 



Robust flies of medium size or smaller, related to 

 Aphamartania Schiner but distinguished by the greatly 

 reduced pulvilli on all legs. Length 12 mm. 



Head, lateral aspect : The face is not produced beyond 

 the base of the antenna ; it is nearly straight in profile, 

 or slightly convex, the lower portion of the face visible 

 because of the posterior recession of the eye, the upper 

 portion nearly plane with the eye. The eye is convex 

 anteriorly and strongly convex behind, receding both 

 anteroventrally and anterodorsally. The occiput is 

 thick but especially medially; it slopes gradually out 

 to the eye margin, both laterally and dorsally. The 

 pile of the occiput is dense and coarse, longer ventrally 

 and everywhere partaking of the character of weak 

 bristles; it is arranged in 5 or 6 very irregular rows 

 and therefore quite numerous. These elements be- 

 come stouter and more prominent along the middle of 

 the eye margin and especially stout dorsally and behind 

 the vertex. All are pale and nearly straight, bluntly 

 tipped. The proboscis is relatively short, though it ex- 

 tends well beyond the face; it is robust, gradually 

 swollen towards the base both dorsally and laterally 

 with a prominent dorsomedial ridge and the apical por- 

 tion is subcylindrical. The proboscis is directed hori- 

 zontally forward. On the basal half ventrally there are 



