About Bombus eximius Smith, 1852
Bombus eximius Smith, 1852 is a very large species of bumblebee, with distinct size differences across castes: queens measure 28–29 mm (1.1 in) long, female workers measure 14–19 mm (0.55–0.75 in) long, and males measure 18–19 mm (0.71–0.75 in) long. The hair covering its thorax is black, while the hair on its mid and hind tibiae and basitarsus is orange. This bright coloration has also been described as "yellowish red", which translates from the German term gelblichrot. This species can easily be misidentified as Bombus flavescens. Close examination of Bombus eximius’s face shows that the oculomandibular distance (OMD), the distance between the compound eye and the mandible, is 0.9–1.0 times the breadth of the mandible. Its labrum (upper lip) has an irregular lamella that is mostly straight. Large scattered punctures are present along the inner margin of its eye. In terms of ecology, Bombus eximius is relatively uncommon in low-altitude areas between 450–1,200 m (1,480–3,940 ft) around the Sichuan basin. It has been recorded in the Himalayan region, Myanmar, Thailand, Vietnam, multiple regions of China including Yunnan, Tibet, Sichuan, Fujian, Jiangxi, Guangdong, Guangxi, Guizhou, as well as Taiwan and Japan.
