Extracted from: Timberlake P. H., (1960). 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 IV. University of California Publications in Entomology Editors Volume 17, No. 1, pp. 1-156, plates 1-17.|
Beatula is a small, entirely yellow species with dense white hair on head and thorax. It is closely allied to P. bridwelli, which is a dark green and yellow species that visits Sphaeralcea in the deserts of California. In CockerelTs table (1896) beatula runs out at couplet 1 and is much closer to P. luteola than to P. beat a or P. larreae.
Male.—Yellow, unmarked except for the small brownish foveae on sides of frons and lateral margins of tergite 2, and a small black dot in the impression on sides of mesoscutum beneath apex of tegulae. Propodeum tinged with greenish and apical depression of tergites a little whitened; mandibles except rufous tips, labrum, and clypeus slightly paler yellow. Antennae and legs yellow, the claws rufous. Tegulae yellow at base and yellowish hyaline on outer margin. Wings milky hyaline, the nervures pale yellow, subcosta and margins of stigma orange yellow.
Head as broad as long, somewhat broader than thorax, the face depressed, the cheeks about as broad as eyes and unarmed. Facial f oveae oval, twice as long as wide. Mandibles moderately long, tapering, and simple. Abdomen rather broadly ovate and subdepressed. Claws of legs bifid. Stigma of wings of ordinary size and width, and the parts of the marginal cell beneath and beyond stigma about equal. Head and thorax very minutely tessellate and rather shiny, the frons and mesoscutum with fine, close punctures which are obscured by the pubescence. Face below antenna almost polished and impunctate. Abdomen slightly dullish, without evident sculpture. Head and thorax with abundant white hair, that is rather dense for a Perdita, but face below antennae with sparse fine hair; hair of frons and mesonotum shorter than elsewhere, more or less appressed and mosslike. Subgenital plate a little longer than wide and very acutely triangular. Parameral lobes of genitalia as long as the caulis and very slightly clavate at apex as seen from above; sagittae very long, the fused part narrowly fusiform, with the two elements spreading apart at apex; in lateral view the sagittae are moderately curved downward in apical half and blunt at apex. Length, 5 mm.; interior wing, 3.8 mm.