This genus has the dorsal enclosure of the propodeum more or less coarsely rugulate. The terga have short apical areas; usually about 1/3 in the females in terga 2; shorter in males. Males typically have very short antennae; the sixth sternum is often reflexed apically. The genus Trachandrena is closely related but has a transverse ruga cutting off the posterior margin of the dorsal enclosure, facial fovea that are strongly constricted in the lower half or third in females, and the apical areas are greater than 1/2 in terga 2 in females.
For more information, see W. E. LaBerge. 1971. A revision of the bees of the genus Andrena. Part IV. Scrapteropsis, Xiphandrena, and Rhaphandrena. Trans. Amer. Ent. Soc. 97: 441-520.
1. Propodeal corbicula with internal hairs plumose at least in part and with anterior fringe of moderately long, plumose hairs...A. imitatrix
Propodeal corbicula with internal hairs simple, anterior margin without plumose hairs..2
2. Hind femur ventrally with one or two longitudinal ridges or carinae or middle femur with anterior surface strongly concave and ventral margin sharp...3
Hind femur without longitudinal ridge or carinae ventrally; middle femur with anterior surface flat or only gently concave, ventral margin moderately sharp...4
3. Thoracic dorsum with hairs short, thick, scalelike...A. alleghaniensis
Thoracic dorsum with hairs long, pointed, loosely plumose, not at all scalelike...A. atlantica
4. Metasomal terga 2-4 with basal area punctures crowded, separated by less than one puncture width, apical area punctates irregular, separated mostly by one to two puncture widths, often restricted to basal half or slightly more of each apical area at least medially..A. fenningeri
Metasomal terga 2-4 with basal area punctures not usually so crowded, apical area punctures at least as crowded as basal area or more so, not contrasting as in above...5
5. Terga 2-4 with dense apical pale pubescent fasciae but usually interrupted medially; propodeum outside of dorsal enclosure coarsely rugatulopunctate..A. ilicis
Terga 2-4 without pale fasciae or these weak; propodeum outside of dorsal enclosure finely to moderately coarsely punctatorugose...A. morrisonella
1. Hind tibia swollen just below middle so that tibia broader just below middle than at apex..A. imitatrix
Hind tibia not swollen just below middle, broadest at apex..2
2. Sternum 6 with apical margin reflexed...3
Sternum 6 flat, apical margin not reflexed...5
3. Minimum length first flagellar segment as long as second or longer; sternum 2 with apical area equal to at least two-fifths of median length of sternum...4
Minimum length first flagellar segment distinctly shorter than second; sternum 2 with apical area short, usually equal to one-forth of median sternal length or less...A. fenningeri
4. Propodeum outside of dorsal enclosure coarsely to moderately coarsely punctatorugose; ranges along coast from N. Jersey to Florida, west to state of Mississippi..A. atlantica
Propodeum outside of dorsal enclosure moderately coarsely to finely punctatorugose; more interior range..A. alleghaniensis
5. Hind tibia swollen below middle; propodeum outside of dorsal enclosure finely puctatorugose..A. imitatrix
Hind tibiae not swollen below middle; propodeum outside of dorsal enclosure coarsely punctatorugose..A. ilicis
No males of A. morrisonella are known.
County Records: Leon
Locations:
Dates: March 18
Plant:
Notes: New State record for Florida. Previously collected in North Georgia Mountains. This could be a misidentification of Andrena atlantica, as both are in the same species group. The map in LaBerge strongly suggests that A. atlantica is distributed along the coastal plain and A. alleghaniensis is an interior species. If it does occur in Florida, it may be a remnant disjunct population and is probably limited to the eastern panhandle. No photos are currently available at this time.
This primarily northern species has long apical areas in tergum 2 and 3; tergum 2 has apical area at 2/5 length; females have short scalelike scutum hairs; two irregular ridges on the hind femur; male has the sixth sternum reflexed apically.
County Records: Alachua, Baker, Columbia, Escambia, Gadsden, Highlands, Jackson, Lake, Leon, Levy, Liberty, Nassau, Orange
Locations: Gainesville, Highlands Hammock, Orlando, Pensacola
Dates: March 16-May 11; elsewhere mid April to mid May.
Plant: Erigeron quercifolius, Ilex cassine, Nyssa sylvatica, Melilotus alba; elsewhere polylectic with preference for Ilex and Rubus.
Notes: This species is closely related to the more northern and interior species A. alleghaniensis. It can be distinguished from that species by the normal, long barbed hairs on the scutum, the more coarsely sculptured propodeum outside of the dorsal enclosure, and the narrower facial fovea. Males are almost indistinguishable from A. alleghaniensis. These two species may be geographical races or subspecies of one widespread species.
County Records: Gadsden, Jackson
Locations:
Dates: April 2-April 14; across the range March 2-May 24, chiefly in March and April
Plant: Polylectic, preference for Salix and Prunus
Notes: New state record for Florida; previously known from Georgia. Mitchell described the male of this species as A. verna Mitchell. His male of A. fenningeri actually belongs with the species he called A. ilicis. This is an uncommon but widespread species closely related to A. imitatrix and A. morrisonella. Female A. fenningeri can be distinguished by A. imitatrix by the propodeal corbicula lacking plumose hairs anteriorly and having only simple internal hairs. A. fenningeri females have basal area punctures close set in terga 2-4 (often 1) but the apical areas are more sparse and irregularly spaced, especially in the median third of each terga. Male A. fenningeri can be distinguished by A. imitatrix or A. ilicis by the sixth sternum being reflexed apically with the lateral corners of the reflexed margin forming right angles and toothlike.
County Records: Alachua, Baker, Columbia, Duval, Gadsden, Jackson, Levy, Liberty, Okaloosa, Orange, Volusia
Locations: Cassadega, Deland, Gulf Hammock, Jacksonville, Orlando
Dates: Feb., 29-May 17, Feb: 1, March: 4, April:5, May: 1
Plant: Polylectic; Ceonothus microphylla and others.
Notes: Closely related to A. imitatrix. Female A. ilicis can be distinguished from A. imitatrix by the propodeal corbicula having simple internal hairs and being incomplete anteriorly, the propodeum outside of the dorsal enclosure is more coarsely sculptured, the narrower hind tibiae, and the form of the rugulae on the underside of the genal area. The male is very similar to that of A. imitatrix but have a more slender hind tibiae, a more coarsely sculptured propodeum, and slightly longer antennae.
County Records: Alachua, Franklin, Gadsden, Jackson, Leon, Liberty, Okaloosa, Sumter
Locations:
Dates: March 14-April 14, March: 9, April:1; also to early May elsewhere
Plant: Polylectic, often on Rosaceae and Salix
Notes: This includes the subspecies listed in Mitchell (imitatrix, profunda). This species is highly variable characterized by often having red legs (especially the hind legs) in both sexes. The female can be distinguished from other Scrapteropsis by the relatively weak tergal fasciae, the propodeal corbicula almost always having at least a few internal hairs plumose (and the anterior margin hairs plumose) and rather broad hind tibiae. The males have a flat sixth sternum and the hind tibiae is broadest just below the middle.
County Records: Alachua, Orange, Sumter
Locations: Orlando
Dates: March 26-June 25, March: 1, April: 1, June: 1
Plant: Polylectic
Notes: New state record for Florida, previous distribution was furthest south in Georgia. Often confused with other three species (A. imitatrix, A. ilicis, and A. fenningeri). This is a species of dubious status according to LaBerge and it may just be a variant of A. imitatrix or a hybrid between imitatrix and another species. It could be a valid species and may just need more specimens taken to fully characterize it. A. morrisonella females can be distinguished by the broader head, lack of tergal pubescenct fasciae from A. ilicis and from A. fenningeri by the tergal sculpturing.