MYSTACELLA. 51 
Following Schiner, who included Chetolyga, Rond., and Tricholyga, Rond., in the 
genus Nemorea, Meig., it is necessary to notice here various Mexican species which 
have been briefly characterized by M. Bigot :— 
Chetolyga erythropyga, Bigot, Ann. Soc. Ent. Fr. 1888, p. 257. no. 17.—Mexico. 
nigriventris, Bigot, 1. c. no. 18.—Mexico, 
— dubia, Bigot, 1. c. no. 20.—Mexico. 
nigripalpis, Bigot, 1. c. p. 258. no. 21.—Mexico. 
Jlavolimbata, Bigot, 1. c. no. 22.—Mexico. 
albopicta, Bigot, 1. c. no. 23.—Mexico. 
— occidentalis, Bigot, 1. c. no. 25.—Mexico. 
—— nitidiventris, Bigot, 1. c. no. 26.—Mexico. 
enea, Bigot, |. c. p. 259. no. 27.—Mexico. | 
Tricholiga caloptera (sic), Bigot, 1. c. p. 263. no. 53.— Mexico. 
fulvidapex, Bigot, 1. c. no. 54.—Mexico ? 
MYSTACELLA, gen. nov.* 
Head as broad as the thorax; front usually a little prominent ; face perpendicular ; vibrisse at a considerable 
distance above the oral margin, surmounted by some shorter bristles along the inferior part of the facial 
ridges. Eyes hairy, not descending beneath the vibrisse (except in M. rubriventris and M. adjuncta, where 
they extend lower). Antenne elongate, but shorter than the face; third joint at least twice as long as the 
second, usually longer; arista not visibly jointed. Proboscis exserted; palpi cylindrical or filiform. 
Abdomen broadly ovate ; first segment usually shorter than the following; macrochete in the middle and 
on the hind margin of the segments (in some species partly absent). Legs bristly. Wings without a costal 
spine; apical cell opened at some distance before the wing’s tip; curvation of the fourth vein angular, 
without appendice ; posterior cross-vein nearer to that curvation than to the small cross-vein. 
This genus differs from Memorea and Exorista by the vibrisse being inserted at a 
notable distance above the oral margin, and from Nemorea, moreover, by the more 
elongate third antennal joint; from Macquartia by this latter character and by the 
shorter and broader shape of the body. From Brachycoma and Meigenia, which also 
have the vibrissee at some distance above the oral margin, it is distinguished by the 
hairy eyes f. 
The genus contains the following species from Central America :— 
1. Front not at all prominent; eyes descending beneath the 
vibrisse 2 6 6 ew wee ee ee ww ee rUbriventris, v. A. Wulp. 
Front more or less prominent; eyes usually not descending 
beneath the vibrisse . . 2. 1. 1 1 1 ew ee ee 
* povorak (whisker). 
+ Schiner in his synoptic table of the European Tachinine (Fauna Austriaca, Diptera, i. p. lxxiii) has ranged 
Meigenia among the genera with bare eyes. In his description of the genus (J. c. p. 471) he calls the eyes 
hairy, but adds that the pilosity in most species is scarcely visible; Metgenia majuscula, Rond., which has the 
eyes distinctly pilose, may perhaps, therefore, be better placed in Mystacella. 
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