Reprinted with permission of the American Entomological Society from:
LaBerge, W. E., Bouseman, J. K. 1970. A revision of the bees of the genus Andrena of the Western Hemisphere. Part III. Tylandrena. Transactions of the American Entomological Society 96: 543-605.
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This black bee from southern California is related to A. wilmattae and A. hurdi, but not closely. The pronotal humeral angle in coracina is relatively poorly developed but the oblique pronotal suture is sharply impressed, unlike that of hurdi. The female of coracina is unlike that of any other Tylandrena in having entirely black vestiture. The male of coracina is similar in color to that of hurdi but has the first flagellar segment no longer than the second.
FEMALE. MEASUREMENTS AND RATIOS. — N = 3; length, 11-12 mm; width, 3-4 mm; wing length, 4.33-4.83 mm; FL/FW, 0.88-0.89; FOVL/ FOVW, 3.16-3.25.
INTEGUMENTAL COLOR. — Black except as follows: mandible with apical third rufescent; flagellar segments 4-10 dark brown below; wing veins and pterostigma brown to reddish-brown, membranes moderately infumate especially apically; terga 1-3 basally slightly rufescent or piceous; distitarsi rufescent at least apically.
STRUCTURE. — Antennal scape length equals first three and one-half to three and three-fourths flagellar segments; flagellar segment 1 equals in length segments 2 plus 3; segment 2 shorter than 3 and 3 slightly shorter than 4; segments 2 and 3 quadrate or broader than long, 4-10 longer than broad. Eyes each three and three-fourths times as long as broad, inner margins parallel. Malar space, mandible and galea as in perplexa. Maxillary palpus as in perplexa but segmental ratio about 0.9: 1.0:0.8:0.7:0.6:0.6. Labial palpus as in perplexa but ratio about 1.0:0.4:0.3:0.4. Labral process as in perplexa, labrum below process as in wilmattae (with several short, obscure, longitudinal rugulae). Clypeus as in perplexa but longitudinal, median, impunctate line less pronounced, usually reduced to less than half length of clypeus. Supraclypeal area, genal area, face above antennae and facial foveae as in perplexa. Vertex relatively short, above lateral ocellus equal to less than one and one-half ocellar diameters (about as 9:11 or 12).
Pronotum as in wilmattae with humeral angle reduced even more; oblique suture distinctly impressed; surface opaque, finely tessellate. Mesoscutum with small round punctures separated mostly by half a puncture width or less, somewhat sparser posteromedially; surface dulled anteriorly and peripherally by fine shagreening, moderately shiny posteromedially. Scutellum with two large impunctate areas, surface shiny, unshagreened except peripherally. Metanotum and propodeum as in erythrogaster but dorsal enclosure of propodeum almost entirely finely rugatulopunctate. Wing veins as in erythrogaster. Tergum 1 with apical area punctate in basal two-thirds, punctures small, separated mostly by two to three puncture widths; basal area punctures separated mostly by three to four puncture widths or more; surface shiny, unshagreened or finely so. Terga 2-4 with apical areas punctate in basal half to three-fourths, punctures minute, separated mostly by two puncture widths; basal area punctures larger, separated mostly by one to two puncture widths; surface shiny, reticular shagreening present but fine. Pygidial plate and sterna as in perplexa but sternal punctures more crowded.
VESTITURE. — Entirely black in color. Propodeal corbicula without long plumose hairs anteriorly. Dorsal thoracic hairs short.
MALE. MEASUREMENTS AND RATIOS. — N = 2; length, 11-12 mm; width, about 3 mm; wing length, 4.13-4.35 mm; FL/FW, about 0.88; FS1/FS2, 0.89-0.96.
INTEGUMENTAL COLOR. — Black except as follows: mandible with tip rufescent; flagellar segments 2-11 dark brown below; wing veins and pterostigma reddish-brown, membranes slightly infumate; distitarsi somewhat rufescent apically.
STRUCTURE. — Antennae moderately long, in repose reaching middle of scutellum; scape length equals first two and one-half flagellar segments or slightly more; flagellar segment 2 extremely slightly shorter than segment 3, segments 2-11 longer than broad. Eyes each about three and one-fourth times as long as broad, inner margins parallel. Malar space, mandible and galea as in female. Maxillary palpus as in perplexa but segmental ratio about 1.0:1.0:0.7:0.7:0.6:0.6. Labial palpus as in perplexa but ratio about 1.0:0.5:0.4:0.4. Labral process as in hurdi. Clypeus short, relatively flat, with crowded small punctures separated mostly by less than half a puncture width, surface moderately shiny medially, with irregular, extremely fine shagreening. Supraclypeal area, face above antennae and vertex as in female. Genal area as in female but slightly broader and shinier.
Pronotum as in female. Thoracic sculpturing as in female but mesoscutum somewhat duller, extremely finely shagreened and lateral surfaces propodeum more punctate and tessellate. Wing venation as in female. Tergal sculpturing as in female except as follows: terga 2-4 with basal area punctures somewhat sparser, apical area with punctures in basal half to two-thirds; tergum 5 like tergum 4 but less punctate; terga 1-5 shinier, shagreening largely absent. Sterna 2-5 with surface as in erythrogaster but only moderately shiny, reticulotransversely shagreened; sternum 6 weakly emarginate apically, without median sulcus, more coarsely shagreened, dull.
Terminalia as figured (Figs. 61-65); note the following: gonocoxite with apical process relatively short, median dorsal lobe relatively short; sternum 7 with median emargination U-shaped; sternum 8 as in mesillae but apical part broader with median short stout hairs more abundant. VESTITURE. — Head hairs white except black along inner margins of eyes, on vertex and mixed with white on upper genal area. Thoracic hairs white except a few black on lower propodeal surfaces. Tergal hairs black except tergum 1 with a narrow band of sparse long white just basad of apical area and tergum 2 with some sparse long white hairs mixed with the dark in basal area. Leg hairs white except hind femora and tibiae with posterior surfaces dark brown, fore and middle tibiae with outer surfaces in part brown, and hind basitarsi with posterior surfaces pale yellow.
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