Extracted from: TImberlake P. H., (1958). 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, Volume 14, No. 5, pp. 303-410, plates 4-15.|
Female.—Similar to ericameriae in color, with the following differences: lateral extensions of clypeus not darkened, the lateral face marks separated from the yellow of clypeus merely by a black sutural line; face with a transverse, yellow Bupraclypeal mark and sometimes a small subantennal spot in each side adjacent to the antennal sockets, the subantennal plates otherwise blackish; legs yellow, the front coxae partly blackish, the small joints of hind tarsi brown and the hind tibiae sometimes with a slight duskiness on part of outer margin; yellow parts of the insect paler, inclining to creamy white, especially on the abdomen, and the dark bands of abdomen blacker; wings whitish hyaline, the nervures pale yellowish, with subcosta and margins of stigma slightly darker.
Head at most only slightly broader than long, somewhat more rotund than in ericameriae. Mandibles broadly dilated within, widest at middle, thence narrowed to the rounded apex, without formation of an inner tooth. Facial foveae a little longer than in ericameriae and separated from the eye margin by about their own width. Sculpture similar, but the tessellation weaker, with the mesonotum almost polished, except around the margins, and somewhat more closely punctured. Pubescence whiter and a little denser, the appressed hair on mesoscutum just in front of seutellum forming a broader band than in ericameriae. Length, 5.5-7 mm.; anterior wing, 4.2-4.7 mm.
Male.—Similar to the male of ericameriae, with the light parts slightly paler yellow. Dark bands of abdomen blacker, with a slight anterior bulge on each side on tergites 2 to 4. Legs yellow, the hind tibiae with an abbreviated brown streak on outer margin and the small joints of hind tarsi brown. Dark band on pronotum contracted to a narrow line on each flank. Yellow marks at anterior end of cheeks and on mesosternum larger or broader than in ericameriae Yellow lateral marks of face ending more broadly above, so that the antennal sockets are about three fourths enclosed by the yellow. Flagellum of antennae orange yellow, becoming narrowly brown above.
Structurally similar to ericameriae, but head only slightly wider than long. Frons less opaque and the mesonotum almost polished and a little more closely punctured. Pubescence somewhat denser and whiter than in ericameriae. Subgenital plate spatulate, with the expanded part widest toward the base and the apex narrower and more rounded than in ericameriae. Aedeagus much as in ericameriae, but the sagittae obtusely angulate somewhat beyond the middle and thence tapering to the acute apex. Length, 5-6.5 mm.; anterior wing, 4-4.4 mm.