Extracted from: P.H. TImberlake. A Revisional Study of The Bees of the Genus Perdita F. Smith, with Special Reference to the Fauna of the Pacific Coast (Hymenoptera, Apoidea Part III). University of Caifornia Press Berkeley and Los Angeles 1958|
Female.—Head and thorax dark, somewhat brassy green, the propodeum a little bluish. Light markings yellow, the legs and abdomen more nearly creamy white. Mandibles except tip, labrum, clypeus except usual dots, supraclypeal and lateral marks, and often subantennal marks yellow. Lateral marks truncate above at lower end of the foveae, and with a spur intruding between fovea and eye margin. Subantennal marks sometimes covering more than half of the plates, or reduced to a small spot adjacent to the antennal socket, or absent. Pronotum entirely yellow or with a dark mark on the flanks. Abdomen with a narrow fuscous band at junction of tergites 1-2 to 4-5, the fourth band sometimes paler than the others. Tergite 1 sometimes with a small dark spot on each side of the basal declivity and more rarely with the median area of the basal half of the declivity partly dark. Legs pale yellow except front coxae, and a brownish tinge on outer margin of hind tibiae and on two or three apical joints of hind tarsi. Scape of antennae and pedicel beneath yellow, the flagellum generally more brownish yellow beneath, the pedical and flagellum otherwise brownish fuscous. Tegulae yellow at base and hyaline on outer margin. Wings slightly whitish hyaline, the nervures and stigma pale yellow.
Head somewhat broader than long, the facial foveae well impressed, broader than the interval between them and the eyes, and somewhat shorter than the space between posterior ocelli. Flanks of pronotum strongly grooved. Pygidial plate moderately broad, more or less ogivally rounded at apex, with a median notch more or less distinct. Length, 4.9-6 mm.; anterior wing, 3.5-3.8 mm.