Reprinted with permission of the American Entomological Society from:
LaBerge, W. E. 1977. A revision of the bees of the genus Andrena of the Western Hemisphere. Part VIII. Subgenera Thysandrena, Dasyandrena, Psammandrena, Rhacandrena, Euandrena, Oxyandrena. Transactions of the American Entomological Society 103: 1-144.
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This species is known from only a few females from California (Fig. 9), but it is so distinctive as to warrant a description at this time. It is very similar and closely related to A. inclinata. The female of declinis differs from that of inclinata chiefly in the form of the propodeum as described below and by the more completely haired corbiculum.
FEMALE. MEASUREMENTS AND RATIOS. — N = 4; length, about 11 mm; width, about 3.5 mm; wing length, M = 3.81 ± 0.137 mm; FL/FW, M = 0.99 ± 0.006; FOVL/FOVW, M = 3.64 ± 0.213.
INTEGUMENTAL COLOR. — Black with same exceptions as in inclinata but pterostigma red in all four specimens before me.
STRUCTURE. — Antennal scape length equal to about first three flagellar segments; flagellar segments as in inclinata. Eyes each almost four times as long as broad, inner margins parallel. Malar space, mandible and galea as in medionitens. Maxillary palpus as in medionitens but segmental ratio about as 1.0:0.9:0.9:0.7:0.6:0.4. Labial palpus as in medionitens but ratio about as 1.0:0.6:0.5:0.6. Labral process and labrum below process as in inclinata. Clypeus evenly convex, with irregularly sized, deep punctures separated by half to one puncture width or more, slightly more crowded basally, surface shiny, unshagreened except basally, without median impunctate line. Supraclypeal area moderately shiny, finely punctate. Genal area in profile broader than eye (but not one and one-half times as broad), laterally with band of minute crowded punctures several punctures in width near eye margin, with small punctures separated by one to two puncture widths elsewhere; surface moderately shiny, delicately shagreened. Vertex as in inclinata. Face above antennal fossae as in inclinata but a few rugulae reach base of lateral ocellus in one specimen (holotype). Facial fovea as in inclinata but slightly broader, separated from lateral ocellus by one ocellar diameter or slightly more.
Thoracic form and sculpturing as in inclinata except as follows: propodeum medially with dorsal surface lacking, inclined convexly from propodeal-metanotal suture; enclosure with delicate transverse rugulae near base, lateral surface with piliferous punctures sparse but scattered throughout. Wing venation and vannal lobe hind wing as in medionitens but pterostigma slightly narrower than from inner margin prestigma to anterior wing margin.
Metasomal sculpturing identical with that of taeniata. Pygidial plate almost U-shaped, apex blunt to rounded, without raised internal triangle but lateral margins slightly upturned unless worn. Sterna as in medionitens.
VESTITURE. — Generally white to pale ochraceous and identical in distribution to that of taeniata except as follows: vertex without dark hairs scopal hairs along posterior margin tibia pale brown; propodeal corbiculum with internal long simple hairs relatively sparse but scattered throughout.
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