Lasioglossum rupticristum McGinley 1986

Lasioglossum rupticristum

TYPE MATERIAL.—The female holotype of L. rupticristum is deposited in the Cornell University Collection. The specimen is in excellent condition and is labeled

ARIZ.[ona] Cochise Co. Chiricahua Mts. Onion Saddle, 7600′ 12 Aug. 1972 G. & K. Eickwort/HOLOTYPE Lasioglossum rupticristum R.J. McGinley.

Twenty female paratypes listed in the “Specimens Examined” section are designated.

ETYMOLOGY.—The species epithet comes from the Latin ruptura (fracture, break) plus crista (ridge) and alludes to the broken pronotal lateral carina, which differentiates this species from the very similar L. heterorhinum and L. lampronotum, which have a complete carina.

DISTRIBUTION (Figure 485).—Lasioglossum rupticristum is known from only 21 females that have been collected from Arizona, Colorado, and New Mexico.

DIAGNOSIS.—The short head (similar to Figure 458), granuloso-punctate anterior third of the mesoscutum (as in Figure 463), and absence of an acarinarium will distinguish L. rupticristum from all other New World Lasioglossum except L. heterorhinum. The pronotal lateral carina of the latter species is complete, whereas that of L. rupticristum is interrupted by an oblique lateral sulcus. Lasioglossum lampronotum is also similar to L. rupticristum but has a shiny mesoscutum with distinct anterior punctures and a complete pronotal lateral carina. Most specimens of L. rupticristum (including the holotype) are unusual in having yellowish orange pubescence (as opposed to white or yellowish brown) and faint metallic tints on the mesoscutum (not visible in all specimens). See L. heterorhinum “Diagnosis” for further details.

DESCRIPTION.—FEMALE: (1) Length 8.0–8.8 mm (x = 8.3, n = 15); (2) wing length 2.3–2.5 mm (x = 2.4, n = 15); (3) abdominal width 2.4–3.0 mm (x = 2.8, n = 15).

Structure: (4) Head short (similar to Figure 458; length/width ratio 0.83–0.92, x = 0.87, n = 15). (7) Supraclypeal area evenly rounded, (8) weakly protuberant. (9) Clypeus projecting approximately 0.65 of its length below lower margin of eyes; (11) surface with obscure median longitudinal sulcation. (14) Distance between lateral ocelli subequal to distance between lateral ocellus and eye. (23) Flagellomere 1 slightly shorter than 2 along dorsal surface. Labrum as in Figure 605; (27) distal keel broad in frontal view, spoon-shaped; (28) distal lateral projections somewhat weakly developed, rounded; (29) fimbrial setae acutely pointed.

(32) Pronotal lateral angle broadly obtuse; (33) pronotal lateral ridge incomplete, interrupted by oblique lateral sulcus; (34) lower portion of lateral ridge narrowly rounded. (35) Mesoscutal lip weakly bilobed, (36) moderately elevated from pronotum. (40) Dorsal surface of propodeum about 0.81 the length of scutellum and about 1.2 times the length of metanotum, (41) slightly depressed centrally, (42) posterior margin broadly rounded; (43) propodeal triangle weakly defined, evident medially as a very low V-shaped elevation with inconspicuous lateral rims, fading towards metanotum; (44) lateral carinae extending at most to midpoint of posterior surface. (45) Tibial spur as in Figure 50.

(46) Lateral edge of metasomal tergum II weakly sinuate.

Sculpture: (47) Face shiny, (48) densely and uniformly punctate between ocelli and antennae, punctures contiguous. (51) Supraclypeal area extremely granulate; (52) punctures separated by their width laterally, becoming sparse centrally, punctures separated by 3–4 times their width. (53) Clypeus mostly polished, obscurely granulate along basal edge; (54) punctation nearly uniform, punctures separated by their width or slightly less. (56) Mesoscutum shiny; (57) punctation as in Figure 463, punctures contiguous laterally, becoming granuloso-punctate anteriorly, less dense centrally, punctures separated by 1–2 times their width. (58) Scutellum sparsely punctate adjacent to median line, punctures 2–3 times their width apart. (63) Dorsal surface of propodeum rugulose (similar to Figure 462); (64) surface obscurely alveolated. (65) Metasomal tergum I moderately shiny; (66) punctation fine, extremely dense, punctures nearly contiguous.

Coloration: (71) Wing membrane hyaline.

Vestiture: (74) Pubescence of head white. (75) Pubescence of thorax white; (76) mesoscutal hairs moderately dense and plumose. (77) Hind tibial hairs concolorous, very pale yellowish brown. (78) Anterior hairs of metasomal tergum I and (79) basal hair bands of terga II–IV white. (80) Acarinarium absent, elongate hairs scattered over anterior surface of tergum I.

FLIGHT RECORDS.—Lasioglossum rupticristum females have been collected from early May through October.

FLOWER RECORDS.—One female taken from Cirsium, and one from Heliopsis (both records from the Chiricahua Mountains, Cochise County, Arizona.

Lasioglossum rupticristum là một loài Hymenoptera trong họ Halictidae. Loài này được McGinley mô tả khoa học năm 1986.