ACROCERID FLIES — SCHLIXGER 373 



Male: Length of entire specimen 8.75 mm.; wing length 6.60 mm. 

 As described for female except as follows: 



Color: Black and brown; head except antennal segment II, 

 pleiirites except spots between sternoplem-a, meropleura, and meso- 

 pleiira, mesonotum except faintly lightened anterior lateral angle, 

 halter, scutellum, and tergites II-V duU black; antennal segment II, 

 spots around sternopleura, anterior lateral angle of mesonotum, 

 tergites I and VI, sternites I-VII, legs, and strong ^^^ng veins dark 

 brown; no orange coloration. 



Pile: Same as in female except that on head about as long as male 

 antennal segment II, that on thorax about as long as male antennal 

 segments I-II combined; pile on abdomen distinctly different, being 

 bicolored, yellowish white and bro\^Ti; on tergite I-II bro"\^Ti except 

 yellowish white near midline, tergite III all brown, tergite IV browai 

 except yellowish white at lateral margins; tergite V has a little brown 

 along base, otherwise yellowish white; tergite VI all yellowish white; 

 all abdominal pile about as long as thoracic pile except that on middle 

 and margins of tergite II, long, nearly as long as front basitarsus. 



Head: With large antennal tubercle placed above mideye height; 

 antennal segment I twice as long, but completely fused, as in female, 

 segment II twice as long in ventral as in dorsal view, much as in 

 capitella (fig. 1,6), segment III missing. 



Thorax: Not maculated, mesonotum slightly lighter colored along 

 anterior and lateral angle; vnng as in figure 3, a except in left wing 

 no crossvein in fu'st posterior cell. 



Abdomen: Longer than thorax, rigid, stigmata as in figure I, a; 

 genitalia missing. 



Holotype: Female; Calacali, Ecuador, altitude 2,800 meters, 1937 

 (F. Campos R.), USNAI 62980. 



Paratype: Male: Same data as holotype, also in USNM. 



Remarks: The type specimens of this species were collected in the 

 same place in Ecuador by the same man, and presumabl}^ on the same 

 date. It has therefore been assumed that the two specimens represent 

 the two sexes of the same species, and it is largely on this evidence 

 that the generic concept taken by the author has been set forth. Since 

 this is the only species of Pialea with both sexes adequately described 

 (see discussion under lomata), the sexual difference in color compli- 

 cates the matter even further. However, on the basis of wing vena- 

 tion and other shared characters, there seems little doubt that the 

 association made in ecuadorensis is correct and not a combination of 

 the sexes representing two species or even two genera. 



This species extends the distribution of Pialea several thousand 

 miles from Brazil and yet, of all the species known to me, it is prob- 



