Reprinted with permission from: Mitchell, T.B. 1962 Bees of the Eastern United States. North Carolina Agricultural Experiment Station Technical Bulletin No. 152. |
QUEEN-—Length 21-25 mm., breadth of abdomen 9.5-11 mm.; black, including legs, spurs and tegulae; wings deeply infuscated, veins testaceous to blackish; pubescence rather short but copious and dense, bright yellow pronotum, tubercles, anterior margin of scutum, and abdominal terga 1-3; scutellum with black or intermixed black and yellow pubescence, and basal tergum more or less intermixed with black; otherwise black over entire head, thorax, legs and abdomen; clypeus doubly punctate, rather closely so laterally and above, with quite coarse and rather close punctures, interspaces with very minute punctures, median line and apical margin to some degree impunctate; labrum broadly rounded or subtruncate apically, a basal protuberance on each side, rather deeply excavated medially, with a subapical, transverse row of rather short, fuscous hairs; inner apical angle of mandible with a pair of rather obscure notches, otherwise rather broadly rounded, outer surface somewhat shining, doubly punctate, with coarse, sparse punctures interspersed with very minute and rather close punctures; malar space smooth and shining, with a few minute, scattered punctures, length about equal to basal width of mandible, about one-fourth length of eye; punctures of face fine and close but deep and distinct medially, becoming somewhat coarser and somewhat more distinctly separated just below ocelli, surface between lateral ocelli and eyes shining and impunctate in part, vertex very finely and densely punctate medially, becoming sparsely punctate laterally; lateral ocelli sub- equally distant from eyes and each other, this considerably less than distance to margin of vertex; scape slightly more than half length of flagellum, basal segment of flagellum considerably shorter than segments 2 and 3 combined; corbicular fringe composed of robust, rather long black hairs, the hind basitarsi very slightly broader at basal third than at apex; tergum 6 narrowly rounded apically. somewhat shining, minutely and rather sparsely punctate toward apex, the broad basal area dull, densely and finely roughened.
WORKER—Length 14-18 mm., breadth of abdomen 6.5-8 mm.; resembles the queen in most details other than size, but thoracic pubescence tends to be more elongate and copious.
MALE—Length 16-22 mm., breadth of abdomen 6.5-8 mm.; black, including legs, spurs and tegulae; wings quite deeply infuscated, veins testaceous to piceous; apical margins of abdominal terga narrowly yellowish-hyaline; pubescence in general quite long and copious, face and cheeks with short, greyish-white pubescence, interspersed with long and erect, black hairs, vertex largely black; pubescence yellow and elongate on pronotum, tubercles, anterior margin of scutum, and pleura adjacent to tubercles, black on posterior two-thirds of scutum, the scutellum, pleura and propodeum with long intermixed black and pale hairs; pubescence largely blackish or dark on legs anteriorly, the posterior fringes more or less pale, fringes on hind tibiae very short and distinctly black on anterior margin, yellowish on the posterior margin; abdominal terga 1-4 densely clothed with elongate and erect, yellow pubescence, 6 and 7 more or less black pubescent on the discs, fringed laterally and on 7 apically with yellowish hairs; tergum 5 is yellow in some specimens, black in others; clypeus closely, finely, deeply and distinctly punctate laterally and above, median apical area shining and impunctate; labrum shining and impunctate across basal margin, otherwise with close, irregular, rather minute punctures, apical margin rather broadly subtruncate, lateral margins rounded; mandibles short and slender, distinctly bidentate apically, the lower tooth more robust than the upper, outer face densely clothed with short, yellowish tomentum, completely hiding the surface, lower margin fringed with elongate, fuscous hairs; malar space smooth and shining, with very minute, scattered punctures, length about equal to basal width of mandible, about one- fourth length of eye; median area of face rather finely and densely punctate, these becoming relatively coarse and well separated toward ocelli, surface between ocelli and eyes shining and sparsely punctate, vertex very closely but rather coarsely punctate medially, becoming somewhat more finely and more sparsely punctate laterally; lateral ocelli very slightly nearer each other than to eyes, sub- equally distant from eyes and margin of vertex; segments 1 and 2 of flagellum equal, segment 3 only slightly shorter than 1 and 2 combined; sterna 7 and 8 and genital armature as shown (fig. 130).
DISTRIBUTION—Quebec to Florida in the East, west to Pacific Coast, throughout season.
FLOWER RECORDS — Aureolaria, Bidens, Cirsium, Cucurbita, Daucus, Eupatorium, Galactia, Hydrolea, Hypericum, Kuhnistera, Liatris, Malus, Medicago, Opuntia, Pontederia, Rhus, Richardia, Rubus, Spiraea, Vernonia and Vicia. Robertson (1929) records this species on the following: Abutilon, Actinomeria, Aesculus, Agastache, Amelanchier, Amorpha, Antennaria, Arctium, Asclepias, Aster, Astragalus, Baptisia, Blephilia, Boltonia, Brauneria, Campanula, Cassia, Cephalanthus, Cerastium, Cercis, Circaea, Claytonia, Clematis, Collinsia, Convolvulus, Coreopsis, Cornus, Crataegus, Crotalaria, Cuphea, Delphinium, Desmodium, Dentaria, Dianthera, Dicentra, Diospyros, Dipsacus, Dodecatheon, Eryngium, Frasera, Gaura, Gentiana, Geranium, Gerardia, Gymnocladus, Helenium, Helianthus, Heliopsis, Heuchera, Hibiscus, Hydrangea, Hydrophyllum, Impatiens, Ipomoea, Iris, Isopyrum, Krigia, Lantana, Leonurus, Lepedeza, Linaria, Lippia, Lithospermum, Lobelia, Lonicera, Ludwigia, Lycopus, Marrubium, Martinia, Melilotus, Mertensia, Mimulus, Monarda, Nelumbo, Nepeta, Oenothera, Orobanche, Oxalis, Pastinaca, Pelatostemum, Pentstemon, Philadelphus, Phlox, Physostegia, Plantago, Podophyllum, Polemonium, Polygonatum, Polygonum, Polytaenia, Potentilla, Prenathes, Prunella, Prunus, Psoralea, Pycnanthemum, Pyrus, Ranunculus, Rhamnus, Ribes, Robinia, Rosa, Rudbeckia, Ruellia, Sagittaria, Salix, Scutellaria, Seymeria, Sida, Silene, Silphium, Sium, Solanum, Solidago, Specularia, Stachys, Staphylea, Strophostyles, Stylosanthes, Symphoricarpus, Tecoma, Teucrium, Tilia, Tradescantia, Triosteum, Trifolium, Uvularia, Verbascum, Verbesina, Verbina, Vernonia, Veronica, Viburnum, Viola, Vitus and Zizia.
The male of pennsylvanicus can be easily confused with that of fervidus (Fabricius). In the latter, however, the malar space is slightly longer than basal width of mandible, and the eyes only about three and one half times length of malar space:
the short greyish pubescence on face and cheeks is much less evident, giving the head a much more definitely black appearance; segment 2 of the flagellum is distinctly shorter than the 1st, and the two combined are distinctly longer than segment 3; the scutellum, pleura and propodeum are definitely yellow pubescent, with no black hairs evident except on posterior surface of propodeum, just below the dorsal triangle; the wings are somewhat less deeply infuscated; the hind tibiae are somewhat more broadly dilated apically, with both the posterior and anterior fringes black.
Reprinted from: LeBerge, W.E., and Webb, M.C. 1962. The Bumblebees of Nebraska. University of Nebraska College of Agriculture-Agricultural Experiment Station, Research Bulletin No. 205
This species is probably the most common in Nebraska. It is found
throughout the state in large numbers.
Female: Head with black pile, some yellow often present on vertex
but vertex never with pile entirely yellow; thorax black at sides, dorsum
yellow anteriorly with interalar band of black pile and scutellum usually
with pile completely black but occasionally with some yellow hairs
intermixed; tergum 1 with pile all yellow or yellow in apical half and
black basally; terga 2 and 3 with yellow pile; terga 4-6 and sterna with
black pile; legs with black hairs.
Male: Head hairs usually entirely black but on face below antennae
and on clypeus often with some white or cinereous hairs intermixed
and vertex rarely with a few yellow hairs intermixed with the black;
thorax yellow with black interalar band; abdomen yellow except last
two terga usually at least partly black above and often entirely black;
legs with hairs dark; outer surfaces of hind tibiae with abundant short
erect or suberect hairs and small punctures obscuring surfaces; eyes not
greatly enlarged, ocelli placed on supraorbital line.
Locality Records. (Fig. 3) Counties: Adams, Antelope, Arthur, Banner,
Blaine, Boone, Box Butte, Boyd, Brown, Buffalo, Burt, Butler,
Cass, Cedar, Chase, Cherry, Cheyenne, Clay, Colfax, Cuming, Custer,
Dakota, Dawes, Dawson, Deuel, Dixon, Dodge, Douglas, Dundy, Fillmore,
Franklin, Frontier, Furnas, Gage, Garden, Garfield, Gosper,
Grant, Greeley, Hall, Hamilton, Harlan, Hayes, Hitchcock, Holt,
Hooker, Howard, Jefferson, Johnson, Kearney, Keith, Keya Paha, Kimball,
Knox, Lancaster, Lincoln, Logan, Loup, Madison, McPherson,
Merrick, Morrill, Nance, Nemaha, Nuckolls, Otoe, Pawnee, Perkins,
Phelps, Pierce, Platte, Polk. Red Willow, Richardson, Saline, Sarpy,
Scotts Bluff , Seward, Sheridan. Sherman, Sioux, Stanton, Thayer,
Thomas, Thurston, Valley, Washington, Wayne, \Webster, Wheeler,
Dates Collected. Queens of Bombus americanorum have been taken
in Nebraska as early as April 25 (Lincoln) and as late as November 10
(Lincoln). Workers have been taken in Nebraska as early as May 14
(Lincoln) and as late as November 12 (Lincoln). Males have been taken
as early as July 12 (Lincoln, Mitchell) and as late as October 3 (Lincoln ). Queens are most abundant in May and June, workers in August and September and males in September and October in Nebraska .