Extracted from: Snelling R.R., (1983). The North American Species of the Bee Genus Lithurge (Hymenoptera: Megachilidae). Contributioun in Science, number 343, pp. 1-11. The Natural History of Los Angeles County, 1983|
FEMALE. Measurements (mm). Head width 3.2, head length 2.7, wing length 7.5, total length 12.
Head. About 1.2 times broader than long; eyes moderately convergent below, upper interorbital distance about 1.2 times lower; malar space linear, without posterior pit. Transverse basal ridge of labrum low, broadly interrupted in middle. Apical margin of clypeus not thickened. Supraclypeal area flat, about 1.4 times broader than long. Clypeus polished between subcontiguous to dense punctures; supraclypeal area broadly impunctate and polished in middle, elsewhere sub-contiguously punctate, interspaces polished. Interocellar dis¬tance slightly less than ocelloccipital distance or ocellocular distance. First flagellar segment shorter than pedicel or sec¬ond flagellar segment; median flagellar segments distinctly broader than long.
Thorax. Anterior half of mesoscutal dorsum sharply scabrous; posterior half of mesoscutum and all of scutellum rugosopunctate.
Color. Blackish brown; legs medium brown; tegula and underside of flagellum ferruginous.
Pilosity. Mostly whitish; reddish hairs along apical margin of clypeus, lower margin of mandible, and inner side of basi-tarsi; first five gastric terga with distinct fasciae of dense, appressed white hairs; posterior margin of pronotum with fascia of white, plumose hairs; discs of terga two through four with sparse, very short, fuscous hairs; fifth segment with conspicuously longer, denser dark hairs; apical segment densely covered with long, dark brown hairs; scopa whitish; all sterna, except last, with conspicuous apical fascia of dense, appressed, white hairs, last segment with brown hairs.
MALE. Measurements (mm). Head width 2.5 to 3.2, head length 2.0 to 2.6, wing length 5.7 to 7.5, total length 8.3 to 10.5.
Head. Head 1.2 to 1.3 times broader than long; eyes moderately convergent below, upper interorbital distance about 1.2 times lower interorbital distance. Labrum with subbasal, median, erect tubercle and with an obsolete ridge extending from base of tubercle to each basal corner. Supraclypeal area flat, about 1.4 times broader than long. Clypeus weakly shiny between continguous to subcontiguous punctures. Supraclypeal area polished and nearly impunctate in middle, with subcontiguous punctures laterad that are coarser than those of clypeus. Interocellar distance a little greater than either ocelloccipital distance or ocellocular distance. First flagellar segment about as long as pedicel, a little shorter than second flagellar segment.
Thorax. Mesoscutum and scutellum with distinct, contiguous punctures.
Color. As described for female.
Pilosity. Similar to that of female, but hairs at apex of clypeus whitish, dark hairs of discs of gastric terga longer; fasciae of second and third terga interrupted in middle; apical fasciae of sterna longer than in female; apical sternite with pale hairs.