Reprinted with permission from the University of Nebraska State Museum from:
Ribble, D. W. 1968. Revisions of two subgenera of Andrena, Micrandrena Ashmead and Derandrena new subgenus (Hymenoptera: Apoidea). Bulletin of the University of Nebraska State Museum 8: 1-124.
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Andrena labergei is very similar to salictaria. It can be distinguished from salictaria by the first transverse cubital vein ending considerably distad of the pterostigma. The male genitalia (figs. 75-77) are quite different from salictaria and are more like ishii.
FEMALE. MEASUREMENTS AND RATIOS. — Length, 8.0 mm; width of mesothorax, 2.1 mm; wing length from. tegula, 6.5 mm; facial length/width, 0.94; foveal length/width, 3.60.
INTEGUMENTAL COLOR. — Color as in illinoiensis except: flagellum dark red-brown below; legs all brown.
STRUCTURE. — Head as in illinoiensis except: middle flagellar segments as long as broad; ultimate flagellar segment slightly more than half again as long as broad; mandible extending to opposite corner of labrum; maxillary palpus with segments in ratio of about 1.5:1.3:1.3:1.2:1.0:1.3; labial palpus with segments in ratio of about 2.0:1.0:1.2:1.2; labral process two-fifths as wide and almost one-third as long as entire labrum, margin not sinuate; clypeus slightly more than half again as broad as long; genal area in lateral view slightly wider than eye.
Mesosoma as in illinoiensis except: scutellar surface with indistinct punctures, reticular shagreening less coarse than mesoscutum; posterior and dorsolateral areas shagreened about like enclosure; metepisternum with shagreening further apart than on propodeal corbicula; posterior hind tibial spur distinctly longer than anterior spur; pterostigma large, nearly twice as wide as prestigma.
Metasoma as in illinoiensis.
VESTITURE. — Hairs as in illinoiensis except: facial fovea amber above; hairs of anterior mesoscutum with fewer branches; hairs of anterior part of propodeal corbicula plumose; apical abdominal fasciae interrupted on terga 2 and 3, hairs only one-sixth as long as exposed tergal length.
MALE. MEASUREMENTS AND RATIOS. — Length, 7.3 mm; width of mesothorax, 2.0 mm; wing length from tegula, 6.2 mm; facial length/width, 0.91; flagellar segment 1/segment 2, 2.00.
INTEGUMENTAL COLOR. — Color as in illinoiensis except: thorax with few slight purplish reflections in addition to blue-black reflections; flagellum all black; stigma dark amber, darker than labergei female; legs all brown or black, not at all light in color.
STRUCTURE. — Head as in illinoiensis except: scape nearly as long as flagellar segment 1-4; segment 1 much longer than 3, twice as long as 2; segment 2 tapered towards base; middle segments longer than broad; ultimate segment slightly more than one and one-half times as long as broad; eye three and one-half times as long as broad in anterior view; inner eye margins distinctly convergent below; max¬illary palpus with segments in ratio of about 1.3:1.3:1.2:1.0:1.0:1.3; labial palpus with segments in ratio of about 4.0:1.5:1.0:3.0; labral process with apex not emarginate; clypeus three-fifths as long as wide, shagreening absent in center; genal area in lateral view as wide as eye; surface between eye and ocelli sculptured like vertex between ocelli.
Mesosoma as in illinoiensis except scutellum sculptured less coarsely than mesoscutum; enclosure of propodeum more coarsely sculptured, with more rugulae basally than in female labergei, Exposed metasoma as in illinoiensis except: tergum 7 irregularly emarginate on posterior margin; sternum 6 with broad apical emargination, lateroapical corners gradually and distinctly bent downward.
Sternum 7 notched at apex, producing two large, rounded lobes; each lobe bearing numerous long, branched setae (fig. 78). Sternum 8 convex, with base expanded into large, irregular plate (fig. 79); apex slightly expanded; shaft bent downward, shaft short, with lateral margins bent abruptly upward; posterior half of sternum with long, plumose setae, some setae reaching slightly beyond apex. Gonocoxite bent downward nearly at right angle; apex a broad, rounded point; dorsal part of apex greatly expanded in lateral view, apex with many weakly branched setae dorsally; dorsal lobes short, broad.
Penis valve large, long, bent slightly anteriorly; apex narrowly rounded, slender; medially greatly expanded in side view, with anterior projecting process on each side (figs. 75-77).
VESTITURE. — Hairs as in illinoiensis.
VARIATION. — Very little variation was noticed in the limited material known of this species. The male from New Mexico has narrower lobes on the seventh sternum and a slightly wider penis valve apex. In the female the labral process may vary from subtriangular to evenly rounded from side to side.