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 California Press Berkeley and Los Angeles 1958, Volume 14, No. 5, pp. 303-410, plates 4-15.|
This is a close ally of zonalis and some of the variants are remarkably similar to zonalis monticola, with which it flies, but the pygidial plate of the female is narrower, with straighter sides, and the mediodorsal lobes of caulis of the male aedeagus are squarely truncate instead of oblique at apex.
This species is dedicated to Dr. 0. H. Swezey, formerly of Honolulu, who accompanied me on a collecting trip to Yosemite where the holotype was taken.
Female.—Head and thorax dark green, becoming more yellowish green on mesonotum. Mandibles except red tips, lateral marks, and sometimes clypeus except usual pair of dots and two brown discal stripes, and more rarely a supraclypeal mark yellow, but more typically the clypeus and area between it and antennal sockets more or less entirely black. Tubercles sometimes confluent with mark on each side of the hind margin of pronotal disk yellow. Abdomen blackish, with a yellow band on tergites 1 to 5, the light bands narrowly interrupted on basal segments and more broadly on tergites 4 and 5, that on tergite 5 sometimes represented by two widely separated marks; or abdomen in paler variants yellow, with a broad dark band at junction of tergites 1-2 to 4-5, the base of tergite 1 yellow with a dark spot on each side, and the yellow bands entire except on tergites 4 and 5 (or tergites 3 to 5). Legs dark, with anterior side of front and middle tibiae, apex of their femora, and the hind trochanters yellow, or the hind femora sometimes yellow on anterior side. Antennae dark, the flagellum dull yellowish beneath, the scape clear yellow beneath, but the pedicel usually mainly dark. Tegulae testaceous hyaline, with the extreme base brownish. Wings dusky hyaline, the nervures brownish testaceous, the subcosta fuscous.
In most structural characters, including sculpture and venation, closely similar to zonalis, but inner tooth of mandibles usually less perfectly formed and pygidial plate comparatively narrow, with lateral margin nearly straight and the apex only Blightly notched. Length, 5.5-6 mm., anterior wing, 3.8-4 mm.
Male.—Head and thorax dark blue-green. Mandibles except red tips, labium, face below level of antennae, except black subantennal plates, tubercles, and mark on each side of hind border of pronotal disk pale yellow. Abdomen yellow, with a blackish band at base of tergite 1 and at junction of tergites 1-2 to 5-6 (or even 6-7); yellow band on tergite 1 interrupted medially as well as one or more, or sometimes all the bands on following segments, and those on tergites 2 to 4 generally broadly and shallowly emarginate behind on each side. Antennae fuscous, or brownish fuscous, the flagellum dull yellowish beneath, the scape broadly paleyellow beneath, but pedicel and terminal joint of flagellum entirely dark. Legs brownish or fuscous, the anterior side of front and middle pair and hind trochanters yellow; or sometimes hind coxae at apex and hind femora and tibiae more or less beneath and on anterior side also yellow. Tegulae as in female, but wings more grayish dusky, with darker nervures.
Head about as broad as long. Mandibles tapering to the acute apex and nearly reaching the far margin of proboscidial fossa. Frons opaquely tessellate and with very fine and obscure punctures. Mesonotum polished, with the minute punctures very remotely scattered. Aedeagus similar to that of sonaliSj but the mediodorsal lobes of caulis squarely truncate at apex. Length, 4.75-5.5 mm.; anterior wing, 3.2-3.5 mm.