NEW MUSCOID FLIES HALL 209 



Remarks. — Described from the type and one male paratype speci- 

 men collected October 4, 1927, by R. C. Shannon. 



In addition to the Argentine specimens described above, I have 

 several Brazilian specimens collected by Dr. S. W. Williston at 

 Chapada (two males from the American Museum of Natural History, 

 and one male from the Aldrich collection now in the United States 

 National Museum), which differ from the Argentine specimens in 

 that they are not bluish metallic on the abdomen. The male genitalia 

 appear to be identical throughout the series, as are also the chaetotaxy 

 and other characters so far as I am able to ascertain. 



SARCOPHAGA TRIDENTATA, new species 



Figure 23 



Male. — Head with front 0.176 of head width; parafrontals and 

 parafacials yellow pollinose, the latter with the usual row of minute 

 bristles below near eye; frontal bristles about 11 in number, the 

 rows diverging below to about the middle of the second antennal 

 segment; orbital bristles absent; outer vertical bristles absent; an- 

 tenna black, third segment two and one-half times as long as second 

 and reaching three-fifths the distance 

 to the vibrissae, which are normal and 

 at the oral margin; arista with long 

 plmnosity for over half its length ; pal- 

 pus and proboscis black, both ordinary ; 

 bucca one-fourth the eye height, with 

 intermixed black and pale hair before 

 the metacephalic suture; back of head 

 with three rows of postocular ciliae, the 

 middle and below with some pale hair. 



Thorax gray pollinose, with the nor- ^^^^^^ 2Z.—8arcophaga tridentata, 



mal three to five black stripes; anterior nevv species: Left lateral view of 



^ ' . male termiuaha. 



acrostichal bristles absent; posterior 



dorsocentral bristles four; sternopleural bristles three; prescutellar 

 bristles one; scutellum with three marginal bristles, one preapical 

 bristle, and one apical bristle. 



Abdomen gray tessellated and with three shifting black stripes; 

 median marginal bristles on the third segment; fourth segment red- 

 dish with a marginal row of about 16 bristles. 



Hypopygium rather small, dark reddish, almost black; both seg- 

 ments somewhat pollinose and covered with numerous black hairs. 

 Genital features as illustrated (fig. 23). 



Wing hyaline; costal spine absent; third costal section as long as 

 fifth and sixth together ; first vein bare ; third vein with several basal 

 setulae. 



