Reprinted with permission of the American Entomological Society from:
LaBerge, W. E. 1973. A revision of the bees of the genus Andrena of the Western Hemisphere. Part VI. Subgenus Trachandrena. Transactions of the American Entomological Society 99: 235-371.
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This small bee is known only from a few specimens from southern Utah. The female resembles sigmundi in the sculpturing of the terga, the short tergal apical areas, and the form of the propodeum. However, the female differs from that of sigmundi and resembles the female of cyanophila in the shiny, coarsely punctate, thoracic dorsum and the narrow facial fovea with relatively broad lower portion. The mesepisternum of the female is unique, as described below, and the vestiture is chiefly pale ochraceous, rather than yellow or red as in cyanophila.
None of the males described below were collected with any of the females, so the association of sexes must be considered provisional. However, nothing of the male morphology precludes this association, the males do not belong to any other known female, and the males were collected in the same general region as the females. Furthermore, some details of sculpture (genal area, mesothorax and propodeum) indicate that the association is probably correct. The male of zionensis is much like that of forbesii but differs in the slightly longer first flagellar segment and the more densely pubescent terga.
FEMALE. MEASUREMENTS AND RATIOS. — N = 6; length, about 6 mm; width, about 3 mm; wing length, M(5) = 3.67 ± 0.204 mm; FL/FW, M = 1.06 ± 0.008; FOVL/FOVW, M = 3.70 ± 0.088.
INTEGUMENTAL COLOR. — Black except as follows: mandible with apical half or more rufescent; flagellar segments 2-10 dark reddish-brown below; tegula piceous; wing membranes hyaline, colorless or slightly milky, veins dark blackish-brown to black; sternal apical areas rufescent; tibial spurs red at least apically; distitarsi dark rufescent.
STRUCTURE. — Antennal scape length equal to first three and three-fourths flagellar segments; flagellar segments as in sigmundi but segments 2 and 3 slightly shorter than broad and segments 4-9 quadrate. Eyes each about three and three-fourths times as long as broad, inner margins parallel. Malar space, mandible and galea as in sigmundi. Maxillary palpus as in sigmundi but segmental ratio about as 1.0:1.0:0.7:0.7:0.7:0.5. Labial palpus as in sigmundi but ratio about as 1.0:0.8:0.6:0.5. Labrum as in sigmundi. Clypeus as in sigmundi but lacking median impunctate line, Supraclypeal areas as in sigmundi but more bulbous and surface shiny, unshagreened. Genal area as in winnemuccana. Vertex above lateral ocellus equal to one ocellar diameter or less, with coarse crowded punctures and fine reticular shagreening, surface dull to moderately shiny. Face above antennal fossae with coarse punctures separated by half a puncture width or less, rugae absent or a few weak rugae present laterally near foveae. Facial fovea narrow above, separated from lateral ocellus by three-fourths to one ocellar diameter, lower portion considerably broader than half width of upper portion and broader than greatest space between fovea and compound eye at that level (much as in winnemuccana or cyanophila).
Pronotum and thoracic dorsum as in cyanophila but mesoscutum more densely punctate posteromedially. Propodeum as in sigmundi. Mesepisternum moderately coarsely punctatorugose except posteriorly where punctures are small and discrete and in small lower area above and in front of coxae where large punctures separated by flattened, more or less shiny spaces (unlike sharp ridges in area above). Tibial spurs normal. Venation as in sigmundi.
Metasomal terga generally sculptured as in winnemuccana but tergum 1 with basal area about as densely punctate as apical area. Pygidial plate as in winnemuccana. Sterna sculptured as in winnemuccana but surface slightly shinier, shagreening more delicate.
VESTITURE. — Generally white or extremely pale ochraceous but facial foveae with internal hairs ochraceous, terga 5 and 6 brown, hind tarsi dark brown to reddish-brown; hind basitibial plate and scopal hairs just below plate brown, and inner surfaces hind tibiae often brown. Terga 2-4 with dense white apical fasciae broadly interrupted medially.
MALE. MEASUREMENTS AND RATIOS. — N = 7; length, 8-9 mm; width, 2.0-2.5 mm; wing length, M = 3.36 ± 0.252 mm; FL/FW, M = 1.09 ± 0.010; FS1/FS2, M = 0.78 ± 0.021.
INTEGUMENTAL COLOR. — Black except as follows: mandible with apical third or less rufescent; flagellar segments 2-11 dark brownish-black below; wing membranes hyaline, only slightly infumate, veins dark reddish-brown; terga with apical rims reddened; sternal apical areas translucent to hyaline; distitarsi dark rufescent; tibial spurs testaceous.
STRUCTURE. — Antenna in repose barely reaching propodeum; scape length equals first two flagellar segments; flagellar segment 1 about three-fourths as long as segment 2 or longer; median segments about one and one-half times as long as broad. Eyes each about three and one-third times as long as broad, inner margins converging towards mandibles. Malar space, mandible and galea as in female. Maxillary palpus as in sigmundi but segmental ratio about as 1.0:1.0:0.9:0.7:0.7:0.7. Labial palpus as in sigmundi but ratio about as 1.0:0.6:0.5:0.5. Labrum as in sigmundi. Clypeus with deep round punctures separated by half a puncture width or less, without median impunctate line, surface shiny. Supraclypeal area similar but punctures smaller. Vertex above lateral ocellus equals less than one to about one ocellar diameter, densely punctate and dulled by dense fine tessellation. Face above antennal fossae finely punctatorugose, longitudinal rugulae indistinct, dulled by fine dense tessellation. Genal areas as in sigmundi.
Pronotum as in female. Mesoscutum, scutellum and propodeum as in sigmundi. Mesepisterna with moderate-sized punctures which are contiguous except posteriorly, surface dulled by fine reticular shagreening. Hind tibial spurs normal. Wing venation as in sigmundi.
Metasomal terga 2-5 with apical areas distinctly less than basal areas medially (on tergum 2 about as 3:5). Terga 1-5 with narrow apical rims impunctate, otherwise with small distinct punctures separated by half to one puncture width (slightly sparser on base of tergum 1 and on tergum 5), surfaces shiny. Sterna 2-5 with apical areas impunctate, basally with minute sparse punctures separated by several puncture widths, surfaces moderately dulled by extremely fine reticular shagreening. Sternum 6 emarginate apically. Terminalia as in sigmundi; see figures 68-69.
VESTITURE. — Generally pale ochraceous to ochraceous, inner surfaces tarsi yellow. Terga 2-5 with apical pale fasciae, often interrupted medially on terga 2 and 3, basal area hairs decumbent and highly plumose and in part appearing like hairs of apical fasciae.
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