Franklin bumble bee (Bombus franklini) is thought to have the most limited distribution of all known North American bumble bee species and one of the most limited geographic distributions of any bumble bee in the world. This species lives in an approximately 13,000 square mile area of the Klamath Mountain region of southern Oregon and northern California. 

Franklin bumble bees are short-tongued, have a small head and their cheeks are shorter than they are wide. In the field, they can be distinguished from similar species in their range by the inverted U-shape pattern of the yellow hairs on the anterior thorax that surrounds a central black patch and extends beyond the bases of the wings. Another distinguishing characteristic is the lack of yellow hairs on the abdomen.