Bumblebees Quick ID

Quick ID
Bumblebees of Southern Ontario

Males have one more abdominal segment than females. All males, except the cuckoo males and the Black and Gold Bumblebee B. auricomus have yellow on the lower face and yellow fringe on underside of thighs (femora).
Identified by yellow/red stripes on abdomen:

One Yellow Stripe:
Common Eastern Bumblebee B. impatiens – segment 1 is yellow.

One and a half Yellow Stripes:
Two-spotted Bumblebee B. bimaculatus – segment 1 yellow; segment 2 yellow is restricted to centre of segment with straight side edges on the yellow stripe, unlike the Brown-belted. Sometimes the male has an additional stripe on segment 4. All three: queen, male and worker have yellow on top of head.

Brown-belted Bumblebee B. griseocollis – segment 1 yellow; segment 2 is yellow to yellowish-brown, restricted to centre of segment with yellow sides rounded and curving up and out to base of the segment.
Note: Male and worker segment 2 are usually yellowish-brown, but this darker colour is not obvious on the queen. Male has very large eyes.

Two Yellow Stripes:
Half Black Bumblebee B. vagans – segments 1 and 2 are yellow. Centre of thorax largely black – larger bees, fly earlier than Sanderson’s Bumblebee B. sandersoni. Sanderson’s is indistinguishable from the Half Black.

Sanderson’s Bumblebee B. sandersoni – segments 1 and 2 are yellow. Centre of thorax largely black – smaller bees, fly later than the Half Black.

Confusing Bumblebee B. perplexus female – segments 1 and 2 are yellow. Thorax completely yellow or with a tiny centre black spot.

Rusty Patched Bumblebee B. affinis – segments 1 and 2 are yellow. Reddish bar on lower border, centre of segment 2. Listed as endangered and restricted to Pinery Provincial Park, Grand Bend in Ontario.

Black and Gold Bumblebee B. auricomus female – segments 2 and 3 are yellow. Segment 1 is black but usually has yellow at side edges. Thorax yellow with a wide black bar between wing bases; lower thorax variable, yellow is mixed with black. Worn workers are easily confused with the American Bumblebee B. pensylvanicus when lower thorax yellow hairs have worn off. Best ID’d by abdominal stripes (American B. pensylvanicus has 3 yellow stripes).

Yellow-banded Bumblebee B. terricola – segments 2 and 3 are yellow; yellow fringe on tip of abdomen. Male may also have yellow on  side edges of last two segments. Thorax has narrower yellow stripe across the segment, before wing bases; rest of thorax black.

Three Yellow Stripes:
American Bumblebee B. pensylvanicus female – segments 1 to 3 yellow. Thorax base yellow; lower half of thorax black, sometimes with a very light sprinkling of yellow. Easily confused with Black and Gold Bumblebee B. auricomus – difficult to tell if first segment is entirely yellow, or just the side edges are yellow.

Black and Gold Bumblebee B. auricomus male – segments 1 to 3 are yellow. Thorax yellow with black bar between wing bases, lower edge of the black bar is V-shaped. Lower thorax has yellow tuft of hair on each side of black V-shape. No yellow hair on underside of thighs (femora).

Confusing Bumblebee B. perplexus male – segments 1 to 3 yellow. Segment 3 usually yellow in centre only. Thorax completely yellow or a tiny centre black spot.

Two-spotted Bumblebee B. bimaculatus male sometimes has a yellow stripe on segment 4 in addition to yellow stripes on 1 and 2.

Four Yellow Stripes:
Yellow Bumblebee B. fervidus female – segments 1 to 4 yellow. Thorax yellow with black bar between wing bases.

American Bumblebee B. pensylvanicus male – segments 1 to 4 yellow.  Segments 5 to tip may have yellow at sides edges; tip yellow. Lower thorax black with yellow fringe at end. Easily confused with the male Yellow Bumblebee B. fervidus which has last 2 segments entirely black.

Tri-colored Bumblebee B. ternarius – segment 1 yellow, 2 and 3 orangish, 4 yellow. Male has yellow at side edges of 5 to tip.

Red-belted Bumblebee B. rufocinctus female – segments 1 and 2 yellow, 3 and 4 orangish. Yellow tufts at side edges of 5.

Five Yellow Stripes:
Yellow Bumblebee B. fervidus male – segments 1 to 5 yellow; last 2 segments entirely black. Thorax yellow with a black bar between wing bases. American Bumblebee B. pensylvanicus male has some yellow on last 2 to 3 segments.

Red-belted Bumblebee B. rufocinctus male – segments 1 and 2 yellow, 3 and 4 orangish. Segment 5 can be yellow or orange. Some can have entirely light yellow stripes on all segments. They have very large eyes.

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