Included here are species with the first two abdominal segments yellow and the remainder black. Half-black Bumble Bee (Bombus vagans) This is a relatively common species that is very hard to distinguish from Sanderson's Bumble Bee. Both have yellow wing pits and some black between the wings. Photo © Kent Mcfarland Perplexing Bumble Bee (Bombus perplexus) Females are often a bold egg yolk color, with a small or non-existent black dot with black wing pits. Males are often bright yellow with yellow hairs on much of their abdomen. Photo © Kent Mcfarland. Sanderson's Bumble Bee (Bombus sandersoni) Very similar to and much rarer than Half-black Bumble Bees. Has a short face. Rusty-patched Bumble Bee (Bombus affinis) This historically common species hasn't been seen in Vermont since 2000. Queens have two yellow abdominal segments, like the other species here. Workers have some rusty coloring on T2.