Lasioglossum jubatum (Vachal 1904)

Lasioglossum jubatum (Vachal)

Halictus jubatus Vachal, 1904:474 [female].—Cockerell, 1905a:90 [key].

Lasioglossum jubatum.—Moure and Hurd, 1986:62 [catalog].

TYPE MATERIAL.—The female holotype is labeled

Museum Paris Mexique, coll. O. Sichel 1867/Mex[ico] [illegible word, probably Sichel] [18]64 [handwritten]/Holotype [handwritten on red label]/jubatus Vach[al] [handwritten]/Halictus jubatus Vach.[al] [handwritten].

This specimen, in the Paris Museum (MNHNP), is missing the fifth tarsomere of the left hind leg and some thoracic hairs are matted, but is otherwise in excellent conditon. The small pin holes in both pleural walls indicate that the type was originally double-mounted and later repinned dorsoventrally.

DISTRIBUTION (Figure 472).—Lasioglossum jubatum is a wide-ranging species known from southeastern Arizona, scattered localities throughout Mexico south to Chiapas, Guatemala, and El Salvador. Twelve males are only tentatively associated with this species and are therefore mapped separately (see “Remarks” section). The localities herein reported from Cochise County, Arizona, are the first records of this species north of the Mexican border.

DIAGNOSIS.—The pale orange to golden hairs of the vertex, pronotum, mesoscutum, scutellum, and metanotum that sharply contrast with the white pubescence of the rest of the head, thorax, and abdomen will distinguish Lasioglossum jubatum from all other known New World Lasioglossum. Additional characters helpful in recognizing L. jubatum are the short head (Figure 473, length/width ratio 0.74–0.92, x = 0.84), granuloso-punctate mesoscutum (Figure 477), and large acarinarium (Figure 478). The pronotal lateral ridge shows some variability in being complete (as in Figure 9) or obscurely notched.

The tentatively associated males can be distinguished from all other know Lasioglossum males by the elongate, rounded, and widely separated hair lobes on the posterior edge of sternum V (Figure 483). Other helpful characters are the short head, complete to virtually complete pronotal lateral ridge, and the conspicuous apicomedial depression of the clypeal surface.

DESCRIPTION.—FEMALE: (1) Length 7.8–10.0 mm (x = 9.1, n = 15); (2) wing length 2.4–2.7 mm (x = 2.6, n = 15); (3) abdominal width 2.6–3.1 mm (x = 2.8, n = 15).

Structure: (4) Head short (Figure 473, length/width ratio 0.74–0.92, x = 0.84, n = 15). (7) Supraclypeal area evenly rounded, (8) moderately protuberant. (9) Clypeus projecting approximately 0.79 of its length below lower margin of eyes; (11) surface with narrow to broad median longitudinal sulcation. (14) Distance between lateral ocelli subequal to distance between lateral ocellus and eye. (23) Flagellomere 1 subequal in length to 2 along dorsal surface. Labrum as in Figure 474; (27) distal keel broad in frontal view, spoon-shaped; (28) distal lateral projections well developed, triangular, not sharply pointed; (29) fimbrial setae acutely pointed.

(32) Pronotal lateral angle broadly obtuse; (33) pronotal lateral ridge incomplete, obscurely interrupted by oblique lateral sulcus to virtually complete; (34) lower portion of lateral ridge sharply edged. (35) Mesoscutal lip very weakly bilobed, (33) moderately elevated from pronotum. (40) Dorsal surface of propodeum about 0.83 the length of scutellum and about 1.4 times the length of metanotum, (41) depressed centrally, (42) posterior margin broadly rounded; (43) propodeal triangle moderately well defined laterally, lateral rims absent, evident medially as a low V-shaped elevation; (44) lateral carinae very well developed but extending only slightly beyond midpoint of posterior surface. (45) Tibial spur as in Figure 35.

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

Sculpture: (47) Face moderately 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 very sparse centrally. (53) Clypeus granulate basally, apical half polished; (54) punctures separated by less than their width basally, less dense and obscure medially to apex, apicolateral areas impunctate. (56) Mesoscutum moderately shiny; (57) punctation as in Figure 477, granuloso-punctate laterally and anteriorly, less dense centrally, punctures 1–3 times their width apart. (58) Scutellum with sparse, fine punctation adjacent to median line, punctures 1–3 times their width apart. (63) Dorsal surface of propodeum (Figure 476) ruguloso-striolate, striae reaching posterior margin; (64) surface obscurely alveolated. (65) Metasomal tergum I moderately shiny; (66) punctation fine, dense, punctures slightly less than their width apart.

Coloration: (71) Wing membrane hyaline.

Vestiture: (74) Pubescence of head white near antennae and on genae, becoming golden on vertex. (75) Pubescence of thorax white on pleuron, propodeum, metathorax and pronotal lobes; deep golden to pale orange on pronotum, mesoscutum and scutellum; (76) mesoscutal hairs dense, conspicuously plumose. (77) Hind tibial hair color differentiated, hairs mostly white, dorsal hairs dark brown basally, brown distally to apex. (78) Anterior hairs of metasomal tergum I and (79) basal hair bands of terga II–IV white. (80) Acarinarium present (Figure 478), a large circular, glabrous area surrounded laterally and dorsally by elongate fringe hairs, dorsal opening of acarinarium wide, width of opening slightly exceeding width of lateral hair fringe as seen in dorsal view.

MALE: Similar to female except as follows: (1) length 7.1–8.8 mm (x = 8.2, n = 10); (2) wing length 2.0–2.7 mm (x = 2.3); (3) abdominal width 1.8–2.3 mm (x = 2.1). (4) Head short (length/width ratio 0.87–0.92, x = 0.90). (5) Gena slightly wider than eye, (6) rounded, not produced posteriorly. (10) Clypeal surface conspicuously depressed apicomedially. Labrum as in Figure 475; (24) distal process moderately well developed, pointed; (25) basal area depressed medially; (26) basal lateral depressions present, weakly developed. (30) Mandible extremely elongate, reaching midway between opposing clypeal angle and eye. (53) Clypeus obscurely granulate, shiny; (54) punctures distinct basally, becoming poorly defined and scattered over apical two-thirds. (68) Clypeal maculation present. (69) Flagellum entirely dark. (72) Tarsi dark, concolorous with tibiae.

Vestiture: (75) Hairs on vertex, pronotum, mesoscutum, metanotum and scutellum white. Sternal vestiture as in Figure 483; (82) Hairs on sternum IV moderately elongate, suberect; (83) surface of sternum V with moderately short, suberect hairs, posterior edge with conspicuously elongate, rounded and well-separated hair lobes.

Terminalia: Sterna VII–VIII as in Figure 479; (85) median process of sternum VIII elongate. Genitalia as in Figures 480–482; (86) gonobase moderately elongate; (87) gonostylus elongate, slender; (89) retrorse membranous lobe moderately broad; (90) volsella with moderately produced lateral lobe.

FLIGHT RECORDS.—Records for L. jubatum females range from March to October, with most records from June to August, with a peak in early July. Eleven of the 12 male records are from July through September; one male was taken on 16 February from the Mexican state of Morelos.

FLOWER RECORDS.—Females (17): Amaryllidaceae 71%; Compositae 24%. Total: 20 in 4 families, 6 genera as follows:

*Agave 12(10); Aplopappus 1; Baccharis 2, 1; Bidens 1; Buddleia 2; Quercus 1.