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"
Ashmeadiella clypeodentala Michener, 1936, Pan-Pac. Ent., 12: 57, 9; Michener, 1936, Nov. Am .Mus., 875: 12 (Key). AshmeadielUa crassa Cockerell, 1924, Proc. Calif. Acad. Sci., 12(4): 558, 9 (part).
This black species is similar to neomexicana but smaller, with the median lobe of the clypeus emarginate at apex in the female.
Female: Inner margins of eyes diverging toward clypeus; flagellum dusky or brown beneath; clypeus coarsely punctate; notches separating median from lateral lobes of clypeus narrow and deep, their sides diverging somewhat apically; lateral lobes of clypeus low and rounded; median lobe short, with median emargination, giving, with the lateral apical angles of the lobe, a four- lobed aspect to the median lobe of clypeus; median lobe of clypeus with a longitudinal carina; median lobe, seen in profile, with upper face at an angle of nearly 1700 to adjacent disc of clypeus; labrum with deep apical emargina- tion; hypostomal carinae each produced to a tooth posteriorly; cheeks nearly as wide as eyes, seen from side; frons and vertex closely punctate; anterior ocellus much posterior to midpoint between bases of antennae and posterior edge of vertex; distance between posterior ocelli slightly greater than distance to nearest eye margin or to posterior edge of vertex. Scutum and scutellum a little less closely punctate than vertex, scutum withl a scarcely perceptable pair of pubescent spots anteriorly; mesepisterna a little more sparsely punctate than scutum; wings clear; inner margin of inner hind tibial spurs serrate with about ten small teeth; outer margin with seven long teeth, the distal one and the basal two of which are shorter than the others; inner margin of outer spurs with four small teeth, basal two largest, outer margin with six small, oblique teeth. Abdomen nearly as coarsely punctate as scutum, punctures close, or on anterior tergites dorsally separated by nearly half a puncture width; tergites one to five with distinct apical bands of white pubescence; scopa dull white, sparse. Length 6 to 7 mm.
Male: Similar to female; lower parts of inner orbits diverging toward clypeus; clypeus mostly rather coarsely but closely punctate, subapical part finely and closely punctate, apical margin medially shining and impunctate and with a rather distinct, slightly crenulate emargination about half as wide as basal width of clypeus and demarked by distinct angles; labrum with apex slightly emarginate; cheeks a little over half as wide as eyes, seen from side; distance between posterior ocelli considerably greater than distance to eye margin or to posterior edge of vertex. Scutum sometimes distinctly more finely and sparsely punctate than vertex; inner margin of inner hind tibial spurs with about eight small teeth, outer margin with five long ones; inner margin of outer spurs with three small teeth, outer margin with four very small, oblique teeth. Lateral teeth of sixth tergite rather large, sometimes partly testaceous; median teeth small, testaceous, about as long as broad although somewhat variable, concavity between them a little deeper than a semicircle. This species is found in the deserts of southern California and Lower California. The male is here described for the first time.
CALIFORNIA: five miles west of Indio, April 10, 1936, on Prosopis glandulosa (C. D. Michener); Dos Palmos, Riverside County; Box Canyon, March 31, 1934 and April 14, 1935, on Cercidium forrevanum (P.H.Timberlake); Painted Canyon, April 18, 1925, on Prosopis glandulosa and Cercidium torreyanum (P.H.Timberlake); Palm Springs, April 9, 1934, on Cercidium torreyanum (P.H.Timberlake).