112 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 115 



Of all the Nearctic species of Tanypus this one most closely 

 resembles T. punctipennis Meigen (Edwards).^ 



It differs most noticeably by having a smaller and darker tubercle 

 on the mesonotum and by having a more strongly produced mesial 

 carina on the dististyle of the male genitalia. It is distinguished from 

 other Nearctic species in the key (p. 120). 



Tanypus imperialis, new species 



FlGUKES 4o-C 



Holotype male: USNM 65516, Laguna Lake, Imperial Co., June 

 9, 11, 1950. 



Head with about 12 clypeal bristles; palpi 3-segmented, ratio 

 (length times width) 20 x 16:23 x 12:25 x 10. Antennal ratio 2.04 (in 

 paratype collected with holotype; antennae missing on holotype). 



Head and thorax largely yeUow; mouthparts, antennal pedicel, 

 vittae, and postnotum shining cinnamon brown. Pronotum strongly 

 produced; mesonotal tubercle yeUow. Halteres white. Wing spots 

 small and pale. Wing length 2.32 mm. ; venarum ratio 1.03. Prealar 

 bristles 3; dorsolateral bristles in single row; scutellar bristles 6 in 

 posterior transverse row; anterolateral bristles absent. Fore tarsal 

 beard 6 times tarsal diameter; legs yellow, fore femur, extreme tip of 

 tibia, and tips of tarsal segments 1 to 4 with preapicle brown band; 

 tarsal segment 5 largely brown; mid and hind femora with distinct 

 preapical brown band, second indistinct brown band below that, two 

 separated by clear j^ellow band; remainder of legs as fore leg. Fore 

 tibia mth simple spur, no side barbs; spur length : diameter of tibial 

 apex 37:48. Middle tibial spurs slightly curved, with 2 side barbs 

 long and fihform; spur length ratio 30:30. Hind tibial spurs as 

 middle leg, ratio 32:40; no comb. 



Leg proportions: 



Abdomen yellowish brown, with middorsal, longitudinal brownish 

 streak near base of each segment. Ninth tergite with 15 bristles; 

 medially directed bristles of basistyle almost uniform in size; dististyle 

 with unique, incurved, lameUa-like tip bearing small, subapical spur. 



3 The status of Tanypus punctipennis Meigen of American autliors was somewhat uncertain due to the 

 brevity of published descriptions. In lieu of type examination, I have examined a series of specimens 

 kindly loaned to me by Dr. Paul Freeman from the collections of the British Museum (Natural History). 

 The specimens were determined by F. W. Edwards, who had examined the Meigen types in Paris. T. 

 punctipennis Meigen (Edwards) has proven to be different from the specimens described under this name 

 in American Uterature. To clarify the status of this species I have given a more complete description of 

 Edwards' material in an appendLx to this paper. 



