Reprinted with permission of the American Entomological Society from:
Bouseman, J. K., LaBerge, W. E. 1978. A revision of the bees of the genus Andrena of the Western Hemisphere. Part IX. Subgenus Melandrena. Transactions of the American Entomological Society 104: 275-390.
Please report text errors to: leah at discoverlife dot org.
This uniquely colored species of Melandrena is known from a few specimens from Louisiana and Texas. Both sexes of dolomellea are marked by the metasoma and legs being largely ferruginous. The female has an orange clypeus and more or less red to orange markings on the head and thorax. The female has the propodeal sulcus spindle-shaped (somewhat narrowed at both ends) and deeply infumate wings.
FEMALE. MEASUREMENTS AND RATIOS. — N = 5; length, 12-13 mm; width, 3.5-4.0 mm; wing length, M = 5.20 ± 0.253 mm; FL/FW, M = 0.94 ± 0.009; FOVL/FOVW, M = 3.08 ± 0.060.
INTEGUMENTAL COLOR. — Head black except mandible rufescent. clypeus and lower surface scape orange; pale specimens with supraclypeal area, parocular areas, face surrounding antennal fossae, flagellar segment 1, lower two-thirds of genal area, and small macula on vertex above median ocellus suffused with red or orange. Tegula translucent, yellow. Wing membranes deeply infumate, brownish-black, veins deep reddish-brown. Thorax entirely black in one specimen; palest specimen with posterior pronotal lobe, median part of mesepisternum, upper part of metepisternum, propodeal dorsal enclosure and narrowly outside of enclosure red to orange; intermediate forms occur. Metasoma entirely bright reddish-orange except apical areas of terga and sterna yellow-hyaline in palest specimen; darkest specimen with basal tergum brown, apical areas terga 2-5 brownish-red and apical half or more of basal area of each sternum reddish-brown; intermediate specimens have all terga with apical areas translucent brown, basal areas orange-red with more or fewer dark spots especially laterally. Legs bright orange-red except trochanters and coxae reddish-brown.
STRUCTURE. — Antenna, eyes, malar space and galea as in vicina. Maxillary palpus as in vicina but segmental ratio about as 0.9:1.0:0.8:0.7:0.7:0.6. Labial palpus as in vicina but ratio about as 1.0:0.6:0.5:0.5. Labral process small, weakly emarginate apically, trapezoidal, depressed basal half with three or four transverse striae; labrum below process with weak transverse sulcus and two or more poorly formed cristae. Clypeus with coarse punctures separated by half a puncture width becoming smaller posteriorly, with median impunctate line; surface shagreened, dull except in apical half or less. Supraclypeal area as in vicina but one specimen with depression at upper end of area. Face above antennal fossae, facial fovea, vertex and genal area as in vicina.
Thoracic form and sculpturing as in vicina except as follows: scutellum and mesoscutum posteromedially moderately shiny, shagreening present but weak; propodeum with dorsal enclosure roughened throughout by irregular rounded rugulae or lumps; propodeal posterior surface with longitudinal sulcus slightly narrowed above as well as below, spindle-shaped. Wing venation, tibial spurs and tarsal claws as in vicina.
Metasomal tergum 1 with basal area with small sparse punctures separated by two to five or more puncture widths; apical area, except impunctate rim, with large punctures separated by half to one puncture width; surface moderately dulled by reticular shagreening. Tergum 2 with basal area with small round punctures separated by half a puncture width or slightly more; apical area with similar punctures but slightly more crowded except in impunctate rim; surface shiny 10 moderately shiny, reticular shagreening delicate. Terga 3 and 4 similar to tergum 2. Pygidial plate broad, V-shaped with broad rounded apex. Sterna sculptured as in vicina.
VESTITURE. — Generally ochraceous but inner surfaces tarsi pale yellow and dorsum of thorax usually fox-red. Form and distribution of hair as in vicina but mesoscutal hairs short, decumbent, sparse posteromedially.
MALE. MEASUREMENTS AND RATIOS. — N = 1; length, 11 mm; width, 2.5 mm; wing length, 4.00 mm; FL/FW, 0.87; FS1/FS2, 1.00.
INTEGUMENTAL COLOR. — Head black but mandible dark rufescent, scape with lower surface faintly rufescent apically and flagellum below dark brown. Tegula translucent, yellow; wing membranes moderately infumate, brownish, veins dark reddish-brown. Metasomal terga and sterna yellow-orange except as follows: base of tergum 1 brown; tergum 2 with a small brown macula on either side; terga 1-6 with apical areas hyaline, yellow, brownish at bases; sterna 2-5 with apical areas hyaline, faintly yellow. Legs orange except dark reddish-brown trochanters and coxae.
STRUCTURE. — Antennae in repose reaching midscutellum; scape length equals first two and one-half flagellar segments; flagellar segments as in vicina. Eyes each three and three-fourths times as long as broad, inner margins converging slightly toward vertex. Mandible, malar space and galea as in female. Maxillary palpus as in vicina but segmental ratio about as 0.8:1.0:0.7;0.7:0.6:0.5. Labial palpus as in vicina but ratio about as 1.0:0.7:0.5:0.5. Labral process bidentate apically, depressed base with three transverse striae, shiny; labrum apical to process without sulcus or cristae. Clypeus with shallow punctures separated by half a puncture width and becoming smaller posteriorly, without median impunctate line; surface lightly shagreened, more densely basally. Supraclypeal area, face above antennal fossae, vertex and genal area as in female.
Thoracic form and sculpturing as in female but mesoscutum dull posteromedially, propodeum with surface outside of enclosure roughened by punctures, propodeal posterior surface with sulcus linear, not spindle-shaped. Wing venation, tibial spurs and tarsal claws as in vicina.
Metasomal terga 1-5 sculptured as in female terga 1-4 but punctures slightly sparser and shagreening denser especially at bases of terga 2-5. Sterna 2-5 as in vicina. Sternum 6 with apical margin shallowly emarginate apically.
Terminalia as in figures 99-103; note sternum 7 almost hairless apically and sternum 8 with rounded apex.
VESTITURE. — Generally pale ochraceous but inner surfaces tarsi pale yellow. Form and distribution of hair as in vicina.
|
