This subgenus is closely related to Scrapteropsis. It has vernal or early summer bees primarily associated with Prunus, Salix, and other trees and shrubs. Most species are polylectic. Females are distinguished by having narrowed facial fovea in the lower half, dorsal enclosure of the propodeum is coarsely rugose, set off by a transverse carina; metasomal terga 2-4, especially 2, with apical depressed area equal to 1/2 of the tergal length (may be less but more than 1/3); coarse sculpturing. Males have similar propodeal features as the females and long tergal apical areas. They also have a distinctive genital capsule.
For more information, see W. E. LaBerge. 1973. A revision of the bees of the genus Andrena of the western hemisphere. Part VI. Subgenus Trachandrena. Trans. Amer. Ent. Soc. 99:235-371.
Punctures of tergum 1 and 2 close, deep and quite coarse, interspaces not exceeding their diameters..A. forbesii
Basal abdominal tergum shining and punctures minute, irregular and sparse over most of disc..A. hippotes
Basal abdominal tergum closely, deeply and rather coarsely punctate, interspaces not much exceeding diameter of punctures..A. forbesii
Basal tergum shining, punctures fine and close; hind tibiae and all tarsi testaceous...A. hippotes
County Records: Leon, Sumter
Locations:
Dates: June 25;
Plant: Polylectic, primarily on Rosaceae and Salicaceae
Notes: New state record for Florida, previously known from Georgia. Mitchell described A. pyracanthae as a new species, is actually a synonym of A. forbesii.
County Records: Alachua, Liberty, Sumter
Locations:
Dates: March 26-June 25, March: 2, June:1
Plant: Polylectic, preferring Rosaceae and Salicaceae
Notes: New state record for Florida, previously known from Thomasville, GA. Mitchell described A. arenakensis as a new species, is actually a synonym of A. hippotes.
These two species listed above may hybridize in nature. Occasionally individuals with characteristics of both species have been found.
