HELEOMYZID FLIES NORTH OF MEXICO—GILL ay Wd 
This genus is distinguished from related genera by a single ventral 
apical bristle on the middle tibia, three pairs of dorsocentral bristles, 
and the ending of the first vein of the wing at or very near the level 
of the anterior crossvein. 
Key to the Species of Tephrochlamys 
Scutellum and legs wholly yellow. . ...... . .. . flavitarsis Darlington 
Scutellum and legs not wholly yellow . ...... . . = rufiventris (Meigen) 
Tephrochlamys rufiventris (Meigen) 
Figure 18 
Helomyza serrata Linnaeus, Fallén, 1820, p. 4 (part). 
Helomyza canescens Meigen, 1830, p. 57. 
Helomyza rufiventris Meigen, 1830, p. 58. 
Helomyza nigricornis Meigen, 1838, p. 369. 
Heteromyza rufipes Zetterstedt, 1838, p. 764. 
Helomyza laeta Zetterstedt, 1838, p. 766; 1847, p. 2452. 
Tephrochlamys rufiventris (Meigen), Loew, 1859, p. 77.—Pandellé, 1901, p. 353.— 
Aldrich and Darlington, 1908, p. 72.—Czerny, 1924, p. 85; 1927a, p. 27.— 
Collin, 1943, p. 242. 
Lerva laeta (Zetterstedt), Rondani, 1867, p. 128. 
Tephrochlamys rufiventris var. nigriventris Strobl, 1906, p. 353. 
Maue.—Front reddish orange; fronto-orbital plates, ocellar triangle, 
and vertex cinereous, pollinose; lower half of head, including face 
and cheeks, yellow; antennae reddish brown, aristae dark brown to 
black, minutely pubescent; brownish area between antenna and eye; 
anterior fronto-orbital bristle about % to %4 the height of the posterior 
bristle; oral vibrissae strong, a single row of buccal setae; a bristle 
on the postgenal area in addition to setae; cheek-eye ratio from 
0.43 to 0.55. 
Thorax blackish in ground color with a gray pollinosity; scutellum 
may be yellowed at the apex, otherwise concolorous with the remainder 
of the thorax; dorsocentrals 0+3; prescutellar bristles present; 
scutellum bare except for 2 pairs of lateral bristles; propleural bristle 
present; mesopleuron bare except for 1 or more small setae near the 
propleural bristle; sternopleural bristle present, a few small setae 
anterior to the bristle, longer hairs between the coxae; remainder of 
pleura bare; prosternal bristles absent. 
Legs yellowish orange, becoming dark brown distally; forefemora 
darkened; middle tibia with 1 ventral apical bristle; tibia with dorsal 
prespical bristle present. 
Wings hyaline; coastal spines present, but relatively short. 
Abdomen yellow with uniformly scattered setae; segments 3-5 with 
a row of bristles posteriorly; terminalia small. 
FrmaLe.—Similar to male except for terminalia. 
