HORSEFLIES OF THE SUBFAMILY TABANINAE 19 
pale-yellow hair above wing base; scutellum entirely dark brown. Pleura and 
coxae yellowish gray, with white hair. Wing hyaline, the costal cell and 
margin of vein Ri; brown; venation normal. Legs orange brown, fore tibia 
apically and tarsi darker; hair of legs mostly yellowish brown, the hairs of 
hind tibial fringe short and sparse. 
Abdomen dark brown, with narrow, light-yellowish-gray bands on hind margins 
of tergites 1-6, the first band slightly wider than others; second tergite with a 
median triangle of same color, narrow anteriorly and nearly reaching anterior 
margin; venter brownish gray, with median dark spots anteriorly on sternites 
3-7. 
Male.—Unknown. 
Type.—Female, Ohio State University. Paratype, United States 
National Museum No. 50612. 
Type locality—tLargo Key, Pinellas County, Fla. 
Distribution—Duval and Pinellas Counties, Fla. March 4 (Largo 
Key) to March 8 (Gulfport). In the United States National 
Museum, one female. 
The Genus ATYLOTUS Osten Sacken 
Atylotus Osten Sacken, Mem. Boston Soc. Nat. Hist. 2 (pt. 4, No. 4) : 426, 1876. 
(Genotype, Tabanus bicolor Wiedemann. ) 
Ochrops Szilady, Ent. Mitt. 4: 93, 1915. (Genotype, Tabanus plebejus Fallen.) 
Dasystypia Enderlein, Mitt. Zool. Mus. Berlin 10: 347-348, 1922. (Genotype, 
Tabanus rusticus Linnaeus. ) 
Generic characters.—Small yellowish or grayish species; eye pilose and 
usually with a Single, diagonal, purplish band; large and small facets in eye of 
male moderately to sharply differentiated ; no ocellar tubercle; median and basal 
calli absent or much reduced; second palpal segment of female stout basally. 
Although this was originally proposed as a subgenus of Z'abanus, 
it is the writer’s opinion that the characters are sharply enough 
defined to warrant generic status. The genus Ochrops Sailady, based 
upon 7’. plebejus Fallen and related species, was correctly placed as a 
synonym of Atylotus by Enderlein. Krober (8) placed 7. tricolor 
Zeller and related species under Atylotus, but improperly, for tricolor 
is the type of the genus Z’herioplectes Zeller and is very different from 
T. bicolor Wiedemann. 
Key to Females of Nearctic Species of Atylotus 
1. Antenna black; tibiae bicolored_____-____ pygmaeus (Williston), p. 20. 
Antennasyellows too brown ; tibiae unicolorous_.s__—_=_-____-_____-_____ Pe 
PPK Tonsil henor denuded *callie 2 23 oe er ee 3 
Frons with one or more small, denuded ealli 
insuetus (Osten Sacken), p. 20. 
Pe leumaryellowweeas > ote tolls Sees bicolor (Wiedemann), p. 22. 
JESU EAE A he OE Re 4 
4. Pale hair of abdomen white; frons moderate in width; basal portion of 
third antennal segment stout, with dorsal angle prominent and 
near middlevotdength: = ohioensis (Hine),.p. 22. 
Pale hair on dorsum of abdomen bright yellow; frons usually rather 
narrow; basal portion of third antennal segment moderately elon- 
gate, the dorsal angle slight and basad of middle__________--___- 9) 
5. Pale hair of venter nearly white; palpus with abundant black hair ; 
usually over 10 mm in length_________ pemeticus (Johnson), p. 23. 
Pale hair of venter as yellow as hair of dorsum; palpus with long 
white hair predominant, the black hair sparse; usually under 10 
Oma Th ON (era ea ea ra aa a DN ee ee thoracicus (Hine), p. 24. 
Suitable characters for use in a key to separate the males have not 
been discovered, but in most cases the coloration and general appear- 
ance will serve to associate them with their females. 
Ce 
