Extracted from: Timberlake P.H., (1962). 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 V. University of California Publications in Entomology Editors, Volume 28, No. 1, pp. 1-124.|
This is another segregate of the forms allied to mentzeliae and is perhaps most closely related to mentzeliarum: many females have the clypeus white, as does that species, and consequently are difficult to distinguish. They are somewhat smaller and have slightly shorter lateral face marks. The males, on the other hand, agree much better with mentzeliae: some specimens are hardly distinguishable by external characters but differ a little in the genitalia. It is not surprising, therefore, that some females should be misidentified as P. mentzeliarum, as Cockerell has done, and some males as P. mentzeliae.
Cockerell described punctifera in 1914 from females collected at Stone Cabin Canyon, Santa Rita Mountains, Arizona, at flowers of Gossypium thurieri, and identified part of his material as P. mentzeliarum. Since that time many punctifera have been collected in Arizona at flowers of Mentzelia pumila. Their activity, like that of allied species visiting this plant, is synchronized with the opening of the flowers, which takes place about an hour before sundown in midsummer. On the mesa west of Blythe, California, an annual form of Mentzelia pumila that blooms at the end of April opens its flowers in midafternoon, with accompanying activity by the Perdita
Female.—Head and thorax dark green; mesoscutum except anterior border, scutellum, meta-notum, supraclypeal area, and subantennal plates, black. Clypeus black, except for a small, white triangular streak at middle of upper border, but varying to pale brown or entirely white. Earely a whitish spot or suffusion on supraclypeal area. Lateral face marks white, triangular, and sometimes hardly higher than wide, but generally reaching nearly to level of antennae, although not intruding between f oveae and eyes. Tubercles, collar of pronotum, and sometimes a small spot on each side of posterior margin of disk, white. Abdomen fuscous above in darkest specimens, with a narrow, enclosed pale-yellow band at base of tergites 2 to 4 or 5, but more commonly having dark color restricted to three or four basal segments, with margins of tergites 1 and 2 remaining dark, or sometimes reduced to four spots on tergite 1 and two subapical spots on one or two following segments; pale color of abdomen generally becoming a testaceous yellow in dried specimens. Legs often pale yellow except hind tibiae and tarsi, but in darker specimens becoming brown or fuscous, except for front and middle pair remaining light at apex of femora, on tibiae except more or less behind, and on tarsi. Antennae pale yellow, with a spot at apex of scape, pedicel and flagellum above, pale brown; in pale examples scape more or less white. Mandibles pale yellow at base and ruf otestaceous on apical half. Labrum dark. Tegulae subhyaline with whitish base. Wings whitish hyaline, nervures paUid, stigma sometimes more or less yellowish.
Head as broad as long. Facial foveae somewhat broader than space between them and eyes, and about two-thirds, or slightly more, as long as space between level of antennal sockets and and anterior ocellus. Mandibles rather stout and blunt at apex, with inner tooth represented by abrupt contraction of width close to apex. Proboscis moderately long, apex of galeae in repose falling short of base of stipites. Venation as in allied species; part of marginal cell beneath stigma generally equal to part beyond, or sometimes part beyond slightly longer. Pygidial plate not much longer than wide at base, plane, and rather narrowly rounded or subtruncate at apex. Sculpture and pubescence as in mentzeliae, head and thorax moderately shining, face and meso-notum almost nude. Length: 4-5 mm.; anterior wing, 3.4-4 mm.
Male.—Similar to male of mentzeliae, but sometimes flanks of pronotum entirely yellow and flanks of propodeum with a slight yellow suffusion. Sometimes with an interrupted and irregular yellow band across anterior part of mesopectus, occasionally extending to pleural region. As in mentzeliae, face yellow to level of antennal sockets with lateral marks going somewhat higher, and cheeks yellow on anterior third to half. Legs yellow, but generally with a slight suffusion of fuscous coloration on hind tibiae and sometimes on hind femora. Abdomen generally orange yellow; tergite 1 more or less entirely fuscous; margins of tergite 2 and apical band on tergite 3, dark, or with dark markings sometimes evanescent.
Head not enlarged or only moderately, much more commonly than in mentzeliae, with cheeks broad, rounded beneath, and unarmed; anterior process of cheeks comparatively weak even in strongly macrocephalus specimens. Structure, sculpture, and pubescence much as in mentzeliae. Subgenital plate somewhat blunter at apex than in mentzeliae. Genitalia similar, but dorsal lobes of caulis less broad at apex and volsellae much more exposed. Length: 3.5-5 mm.; anterior wing, 2.8-3.8 mm.