Aphiochaeta. 371 



115. A. fusca Wood. 



1909. Wood, Ent. Month. Mag. 2, XX, 193, 242 {Pkora). - 1914. Brues, 

 BuU. Wisc. Nat. Hist. Soc. XII, 120. 



Male. Frons considerably broader than high, black, slightly 

 greyish, dull; bristles strong, inner bristle of lower row slightly or 

 almost not below the outer and nearer to it than to the upper supra- 

 antennal; siipraantennal bristles nearly equal or the lower a little 

 weaker; the upper supraantennals nearer together than the inner 

 bristles of middle row, the lower very slightly more approximate. 

 Antennæ black of ordinary size or a little above, arista distinctly 

 piibescent. Palpi brownish yellow to blackish, of ordinary size and 

 armature. Thorax black, a little shining, with blackish brown pube- 

 scence. Mesopleura bare. Abdomen somewhat robust, black, a little 

 greyish, dull; the short hairs rather distinct and longer at the sides, 

 on sixth segment they are longish and at the hind margin elongated. 

 Hypopygium not small, shorter but higher than the sixth segment 

 and when fully exposed somewhat globular; it is greyish black and 

 has numerous short hairs on the sides; below there is a somewhat 

 large, rounded, yellow or dusky yellow ventral plate, not quite reaching 

 to the end of the hypopygium; anal tube short, but high, dusky yellow 

 or brownish. Legs brownish to brownish black, the front legs slightly 

 paler ; hind femora with a row of not long, but distinct and somewhat 

 strong hairs below the basal half, they are densest at the base; also 

 the anteroventral hairs on the apical part somewhat strong; bristles 

 on hind tibiæ well visible, but hair-like and numerous. Wings brown- 

 ish, veins brown or pale brown and strong; costa reaching to the 

 middle, 1 about double 2 and longer than 2 + 3; costal cilia long; 

 angle at fork not large; fourth vein well curved in its basal part, for 

 the rest slightly and evenly curved. Halteres black or blackish. 



Female. Similar to the male; the lower supraantennals smaller, 

 generally half as large as the upper; the hairs below hind femora less 

 pronounced, and the angle at fork generally more acute. 



Length 1,5 to nearly 2,5 mm. 



As jiisca I have determined a species which is somewhat robust, 

 with equal or nearly equal supraantennals in the male, and with the 

 lower supraantennals about half the size of the upper in the female, 

 with costal division 1 about double 2, and with the fork more or less 

 acute, especially in the female; the not small hypopygium does not 

 agree with Wood's description, and he does not mention long hairs 



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