Reprinted with permission of the University of Nebraska State Museum from:|
LaBerge, W. E. 1967. A revision of the bees of the genus Andrena of the Western Hemisphere. Part I. Callandrena (Hymenoptera: Andrenidae). Bulletin of the University of Nebraska State Museum 7: 1-316.
Please report text errors to: leah at discoverlife dot org.
This very small species from the southwestern states seems to be related to A. texana and A. gardineri, although not closely. A. ofella is similar to texana in size, punctation, tergal banding, flagellar segments and the male sixth sternum but differs by being slightly smaller, having a less rugulose dorsal propodeal enclosure without distinct transverse rugulae and by the male clypeus and parocular areas being cream-colored or yellow. A. ofella is similar to gardineri (and especially to A. neomexicana of the gardineri group) in the tergal and sternal banding, the pollen collecting hairs, the bidentate male labral process and in sculpturing but differs in the longer facial foveae of the female, the large pale parocular areas of the male and the flat sixth sternum of the male. Both sexes of ofella differ from gardineri and texana in the front wing having vein 1st m-cu meeting the second submarginal cell well beyond the middle and in the pterostigma being broader than usual in Callandrena.
FEMALE. MEASUREMENTS AND RATIOS. — N = 7; length, 8-9 mm; width, 2.0-2.5 mm; wing length, M = 2.66 ± 0.151 mm: FL/FW, 0.96 ± 0.006; FOVL/FOVW, M = 3.13 ± 0.089.
INTEGUMENTAL COLOR; Black except as follows: mandible with apical half rufescent; flagellar segments 3 or 4 to 10 red below; tegula translucent brown; wing membranes hyaline, veins red to reddish-brown; terga 1-4 with apices narrowly hyaline, rufescent just basad of hyaline margins; sterna 2-5 with apical margins hyaline, more or less rufescent basally; distitarsi rufescent to orange; tibial spurs yellow.
STRUCTURE. — Antennae short, scape length equals flagellar segments 1-4; flagellar segment 1 slightly longer than segments 2 plus 9, segment 2 equals 3 in length and considerably shorter than 4; segments 4-8 quadrate, 9-10 longer than broad. Eye about three 1 one-half times as long as broad, inner margins parallel or converging slightly towards mandibles. Malar space and mandible as gardineri but basoventral angle of mandible weakly developed. pea as in gardineri. Maxillary palpus in gardineri but segmental ratio about 1.2:1.0:0.6:0.6:0.6:0.8. Labial palpus as in gardineri but segmental ratio about 2.3:1.0:0.8:1.0. Labral process trapezoidal, about twice as broad as long, entire or extremely slightly emarginate medially. Clypeus gently rounded from side to side, with small H round punctures separated mostly by half a puncture width except along median longitudinal impunctate area, surface shiny, delicately or not at all shagreened. Supraclypeal area with small crowded punctures, surface moderately shiny, delicately shagreened. Genal area as in gardineri but only slightly broader than eye in profile. Vertex above lateral ocellus equal to one ocellar diameter, sculptured as in gardineri. Face above antennal fossae as in texana but with several rugulae reaching vertex between lateral ocellus and facial fovea. Facial fovea narrow, extends down to level of about middle of antennal fossae, separated from lateral ocellus by slightly less to one ocellar diameter, only narrowly separated from compound eye laterally.
Thoracic structure and sculpturing as in gardineri follows: mesoscutum with small posteromedian area sparsely punctate; mesoscutal and scutellar surfaces shiny, unshagreened; dorsolateral and posterior propodeal surfaces with punctures separated mostly by three or four puncture widths; front wing with vein 1st m-cu meeting second submarginal cell at about two-thirds distance from base of cell; pterostigma as broad or slightly broader than from inner margin of prestigma to wing margin; middle basitarsus parallel-sided, narrower than hind basitarsus medially.
Metasomal terga 1-4 with basal area punctures small, separated mostly by two to three puncture widths, surfaces shiny, shagreening absent or delicate. Pygidial plate V-shaped with narrowly rounded apex, without raised internal triangular area. Sterna 2-5 with narrow apical margin and small mediobasal area impunctate, elsewhere with small punctures separated mostly by two to four puncture widths, surfaces shiny, with delicate, coarsely reticular shagreening. m
VESTITURE; White to pale ochraceous, vertex and thoracic dorsum somewhat darker than below; terga and sternal vestiture as in texana. Pollen-collecting hairs as in texana but propodeal corbicula with plumose internal hairs scattered throughout and tibial scopal hairs long, not shorter apically.
MALE. MEASUREMENTS AND RATIOS. — N = 16; length, 6.0-7.5 mm; width, 1.5-2.0 mm; wing length, M= 2.39 ±0.114 mm; FL/FW, M = 0.98 ± 0.007; FS1/FS2, M = 1.57 ± 0.027.
INTEGUMENTAL COLOR. — Black except as follows: mandible with at least apical third rufescent; clypeus cream-colored or yellow except apical margin and small maculae below and mesad of tentorial pits; parocular areas yellow to level of posterior margin of clypeus and a little higher laterally; flagellar segments 2-11 reddish-brown below; tegula translucent reddish-brown; wing membrane hyaline, veins red to reddish-brown; terga 2-5 narrowly hyaline apically; sterna 2-5 hyaline apically, more or less rufescent basally distitarsi orange to red; middle and hind basitarsi somewhat rufescent apically; tibial spurs yellow.
STRUCTURE. — Antennae short, as in texana. Malar space and mandible as in female but mandible without basoventral angle and subgenal coronet absent. Labral process bidentate but median emargination often shallow, slightly deflected. Clypeus as in female but lacking median impunctate line. Supraclypeal area, genal area and vertex as in female. Face above antennal fossae as in female but longitudinal rugulae not extending onto vertex laterally. Vestige of facial fovea not present.
Thoracic sculpturing and structure as in female except as follows: mesoscutal and scutellar punctures medially separated mostly by three to four puncture widths; propodeum with dorsal enclosure more regularly but finely rugulose. Metasomal tergum 1 with basal area punctures small, separated mostly by two to three puncture widths, surface shiny, unshagreened; terga 2-5 with basal area punctures small, separated mostly by one to two puncture widths, surfaces slightly dulled by fine reticular shagreening. Pseudopygidial area not present. Sterna 2-5 sculptured as in female. Sternum 6 flat, not reflexed apically.
Genitalia and sterna 7 and 8 (Figs. 307-311) as figured; compare with those of texana.
VESTITURE. — Generally white to pale cinereous; distribution of tergal bands as in texana. Sterna 2-5 with subapical fimbriae present but not strongly differentiated from more basal erect hairs.
TYPE MATERIAL. — The holotype (UCB) female, male allotype (UCB) and six paratypes (UCB; INHS) from five miles north of Carlsbad, Eddy Co., New Mexico, were collected on Chrysothamnus sp. by . W. MacSwain, September 21, 1956. Three female and 13 male paratypes (UCB; PHT; AMNH; UAT; INHS) are as follows; ARIZONA: Kirkland Junction, Yavapai Co. 3 males on Gutierrezia microcephala, September 15, 1961, P. D. Hurd. Prescott. 2 females on Aplopappus gracilis, August 31, 1930, P. H. Timberlake. Price (4.8 miles S.). 1 male on Gutierrezia sp. September 7, 1957, P. H. Timberlake. Roadforks (7 miles S.W.), Chiricahua Mts. 1 2, September 23, 1955, C, and M. Cazier. NEW MEXICO: Carrizozo (24 miles N.). 1 male, September 10, 1961, and 2 males, September 12, 1961, on G. macrocephala, P. D. Hurd. Hurley (5 miles S.). 1 male, September 22, 1950, W. Gensch and M. Cazier. TEXAS: Vanhorn (20 miles N.). 1 male on Gutierrezia sarothrae, September 28, 1957, W. Nutting and F. Werner.