The Wisconsin Bumblebee		Sun, Nov 08, 2009

Species		Tongue Length		WI Area		Group		First Appearance Date
								Queens		Workers		Males
affinis		small		both				Apr 21		Jun 17		Jul 27
americanorum		large		southwestern				May 14		Jul 09		Aug 20
auricomus		large		southwestern		*		Apr 30		Jun 25		Aug 3
binaculatus		large		southwestern		*		Apr 21		Jun 5		Jul 10
borealis		large		northeastern		*		May 25		Jun 17		Jul 21
fervidu		large		northeastern		*		Apr 22		Jun 17		Aug 3
grisaocollis		intermediate		southwestern		*		Apr 12		Jun 13		Jul 27
impatiens		intermediate		southwestern		pocket maker		Apr 18		Jun 27		Aug 13
perplexus		small		both		*		Apr 20		Jun 8		Jul 10
rufocinetus		small		northeastern		*		May 28		Jul 1		Aug 7
ternarius		small		northestern		*		Apr 24		Jun 15		Jul 16
terricola		small		northeastern		*		Apr 22		Jun 15		Jul 21
vagans		intermediate		northeastern		*		May 4		Jun 10		Jul 10

Wisconsin Species Key

1.
• Antenna 12-segmented; abdomen with six visible tergites, the tip pointed and inwardly grooved to accommodate a sting (females) ___ (go to 2)
• Antenna 13-segmented; abdomen with seve visible tergites, the tip broadly rounded (male) ___ (go to 3)
2.
• Hind tibia with outer surface concave or flat, smooth and hairless (with a corbicula); abdominal tergites densely convered with hair; apical segement without lateral carinae (bombus) ___ (go to 6)
• Hind tibia with outer serface convex, convered with long hairs (without a corbicula); abdominal tergites clearly visible through a thin coat of hairs; apical segment with vertral carinae (Psithyrus)
3.
• Face usually with yellow hairs, but sometime without; hairs on outer surface of hind tibia sparse and unevenly distributed; genital capsule strongly sclerotized (bombus) ___ (go to 4)
• Face always covered with black hairs; uniformly covering of branched hairs on the the outer surface of the hind tibia; genital capsule weakly sclerotized (Psithyrus)
4.
• Eyes large and bulging out from the sides of the head; ocelli large and place well below the supra-orbital line ___ (go to 5)
• Eyes not bulging out from the sides of the head; ocelli small and placed near the supra-orbital line, above the narrowest part of the vertex (go to 6)
5.
• First three tergites yellow; remainder of the abdomen black ___ auricomus m
• First tergite yellow; basel median protin of second tergite tawny; reminder of abdomen black ___ griseocollis m
6.
• Tergite 1, 2, and 3 with a distinctly contrasting pattern of yellow and red or orange-red hairs ___ (go to 7)
• Tergites 1, 2, and 3 without a contrasting red and yellow pattern; usually only yellow and black; sometimes a scattering of reddish hairs or a male uniformly tawny-red ___ (go to 8)
7.
• Tergites 1 and 4 yellow; 2 and 3 red or orange-red; remainder of abdomen black; pronotum with wide black interalar band, the posterior margin forming a V on the scutellum ___ ternarius f, m
• Tergite 1 yellow, remainder of abdomen with variable red, yellow, and black markings, but on as above; interalar band indistinct and without a V notch on the scutellum ___ rufocinctus f, m
8.
• Tergite 1 yellow, remainder of abdomen black ___ impatiens f, m
• Yellow markings more extensive, at least some yellow on tergite 2 ___ (go to 9)
9.
• Pleura mostly black, the yellow hairs of the thorax not extended much below the wing bases ___ (go to 10)
• Pleura with yellow hairs of thorax extended to bases of legs or nearly so ___ (go to 16)
10.
• Dorsum of thorax with black ___ (go to 11)
• Dorsum of thorax yellow ___ perplexus f
11.
• First four tergites yellow or tawny-red ___ (go to 12)
• First four tergites without a continuous pattern of yellow or tawny-red ___ (go to 14)
12.
• Face densely covered with yellow hairs ___ borealis f
• Face without yellow hairs, at the most with only a few scattered yellow hairs ___ (go to 13)
13.
• Occiput yellow; apex of abdomen black ___ borealis m
• Occiput black; apex of abdomen yellow, red or black ___ ammericanorum m
14.
• Black apex of abdomen with a distinct narrow fringe of yellow hairs ___ terricolo f, m
• Apex of abdomen entirely black, without a fringe of yellow hairs ___ (go to 15)
15.
• Ocelli placed well below the supra-orbital line; occiput with consideraable yellow; scutellum usually with a strong admixture of yellow hairs; tergite 1 black at least in basal middle ___ auricomus f
• Ocelli placed near the supra-orbital line; occiput black; scutellum usually black; tergite 1 with considerable yellow ___ americanorum f
16.
• Tergite 1 yellow, tergite 2 posterior margin black, reminder of abdomen entirely or mostly black ___ (go to 17)
• Tergite 1 and 2 entirely yellow; (if a mail with occiput and face yellow, and tergite 3 black, go to 18) ___ (go to 19)
17.
• Interalar space black ___ rufocinctus f
• Interalar space mostly yellow, usually a few scattered black hairs in the center or a bare spot encircled by black hairs ___ (go to 18)
18.
• Occiput black; tergite 2 black posteriroly, the tawny basal portion broadly curved to lateral margins black, basal median portion yellow ___ bimaculatus f, m
19.
• First four terites entirely yellow ___ (go to 20)
• First four tergites not all yellow ___ (go to 21)
20.
• Interalar space black ___ fervidus f, m
• Interalar space yellow ___ fervidus var dorsalis f, m
21.
• Occiput mostly black; interalar black spot prominent, malar space not longer than its width at apex ___ (go to 22)
• Occiput yellow; interalar space with or without a black spot; malar space as ong as or longer than its width at apex (If a male, go to 23) ___ vagans f
22.
• Tergite 2 with short, stiff yellow hairs, those on base yellow or with a tawny tinge, thos on posterior margin slightly indented at the middle ___ affinis f, m Tergite 2 with shaggy yellow hairs, black intermixed with yellow on posterior margin, and without a distinct median notch ___ rufocinctus f, m
23.
• Tergite 3 black ___ vagans m
• Tergite 3 yellow, sometimes the yellow confined to scattered hairs at the base of the tergite ___ (go to 24)
24.
• Tergite 6 yellow ___ vagans m
• Tergite 6 black ___ perplexus m