Species account taken from: "A Revision of the Genus Ashmeadiella (Hymen., Megachilidae) Author(s): Charles D. Michener Source: American Midland Naturalist,Vol. 22, No. 1 (Jul., 1939), pp. 1-84"
Heriades prosopidis Cockerell, 1897, Ann. Mag. Hist., (6)20:140, 9, nec . Eriades prosopidis Friese, 191 1, Das Tierreich, 28:30, 9 . Ashmeadiella prosopidis Cockerell, 1898, Bull. Denison Univ., 11:64, Y (key); Cockerell, 1898, Bull. Univ. New Mex., 1:64, 9 (key); Michener, 1936, Am. Mus. Nov., 875:8, 9. Ashmeadiella subangusta Cockerell, 1924, Proc. Calif. Acad. Sci., (4)12:588, 9 .
This is a small, slender, sparsely pubescent, black species, closely related to schwarzi and microsoma. It differs from the former by the longer face, from the latter by the broader cheeks.
Female: Inner margins of eyes slightly converging toward clypeus; under side of flagellum dusky; face elongate, facial line as long as transfacial; clypeus rather coarsely and closely punctate; clypeal truncation slightly concave, as long as distance from end of truncation to lateral angle of clypeus; rest of head a little more finely and less closely punctate than clypeus; supraclypeal area more finely punctate than vertex or front; anterior ocellus considerably posterior to midpoint between bases of antennae and posterior edge of vertex; distance between posterior ocelli greater than distance to nearest eye margin, and equal to distance to posterior margin of vertex; cheeks considerably narrower than eyes seen from side, more finely punctate than supraclypeal area. Scutum usually somewhat more coarsely and less closely punctate than vertex; mesepisterna punctured like vertex; inner margin of inner hind tibial spurs with about twelve low, blunt, oblique teeth, outer margin with about eight, blunt, oblique teeth; outer spurs with few, low, blunt, oblique teeth on each margin; tegulae dark testaceous. Abdomen strongly punctured, punctures of dorsum of second tergite separated by about their diameters, punctures of sides of tergites and of apical tergites approximate; tergites one to four with apical bands of pubescence; sixth ternite with transverse coarsely punctate depression, posterior to which is a finely punctate area.
Male: Similar to female; pubescence covering most of face; inner orbits converging below, except for lower parts, where they diverge; transfacial line somewhat longer than facial; clypeus very finely and closely punctate, with di'stinct apical emargination less than half as wide as basal width of clypeus and bounded by distinct angles; distance between posterior ocelli somewhat greater than distance to posterior edge of vertex, distinctly greater than distance to margin of nearest eye; cheeks less than half as wide as eyes, seen from side. Vertex, scutum, and mesepisterna rather coarsely punctate, punctures separated by a little shiny surface; abdomen rather coarsely punctate, punc- tures separated by but little shiny ground, and smaller than those of vertex; lateral teeth of sixth tergite wider than long, angulate apically;.median teeth variable in shape, short, usually rather broad at base, concavity between them broader than a semicircle; teeth of sixth tergite sometimes rufescent. Length 4 mm.
This species is known from the deserts of New Mexico, Arizona, Cali- fornia, and Sonora. It is perhaps oligotropic on Prosopis.
ARIZONA: Tucson (H. G. Hubbard, U.S.N.M.) CALIFORNIA: Potholes, Imperial County, April 7, 1928 (E. P. Van Duzee); five miles west of Indio, on Prosopis glandulosa, April 10, 1936 (C. D. Michener); Andreas Canyon, near Palm Springs, on Prosopis glandulosa, April 10, 1936 (C. D. Michener); Furnice Creek Camp, Death Valley, Inyo County, April 14, 1938, on Pluchea sericea (B. E. White), May 1, 1927 (P. H. Timberlake); Near Mecca, April 13, 1934, on Heliotropium curassa- vicum; Coachella, April 23, 1927, on Prosopis glandulosa; Box Canyon, April 13, 1934, on Acacia greggii; Westmoreland, May 25, 1930, on Salix nigra (all collected by P. H. Timberlake). SONORA: San Jose de Guaymas (L. 0. Howard, U.S.N.M.). Type: female; Mesilla, New Mexico. Ashmeadiella subangusta Cockerell is based on a specimen in which the abdomen is unusually extended.