1897. _Dasypterus ega xanthinus_ Thomas, Ann. Mag. Nat.
Hist., ser. 6, 20:544, December, type from Sierra Laguna,
Baja California.
1953. _Lasiurus ega xanthinus_, Dalquest, Louisiana State
Univ. Studies, Biol. Ser., 1:61, December 28.
_Distribution in Tamaulipas._--Probably occurs in southern
and western parts of state; certainly known only from the
Sierra de Tamaulipas.
Three June-taken females, all captured in mist nets, were lactating.
Hall and Jones (1961:91) assigned all Mexican specimens of the southern
yellow bat to _Lasiurus ega xanthinus_, but remarked that specimens
from western Mexico were paler than those from the east. Of the six
specimens examined from Tamaulipas, four are dark, resembling in color
specimens from Veracruz, Yucatan and Costa Rica, and the other two are
somewhat paler, approaching specimens from Baja California, Zacatecas
and Coahuila. In measurements, Tamaulipan specimens of _Lasiurus ega_
generally resemble specimens from the west, but differ from any other
_L. ega_ seen in having a longer tail, longer ear, and shorter
maxillary tooth-row.
_Records of occurrence._--Specimens examined, 6: Sierra de
Tamaulipas, 10 mi. W, 2 mi. S Piedra, 1200 ft., 4; 10 mi. W,
3 mi. S. Piedra, 1200 ft., 1; 16 mi. W, 3 mi. S. Piedra,
1400 ft., 1.
=Nycticeius humeralis=