Ailurus fulgens was formally described in 1825. The giant panda was not described until 1869, and later took over the unqualified name, forcing this animal to become the red or lesser panda. The two share a bamboo diet and a false thumb, but they are not close kin: the red panda is the sole surviving member of the family Ailuridae, while the giant panda is a bear.
The false thumb is one of the clearer cases of convergent evolution in mammals. In both, a wrist bone, the radial sesamoid, is enlarged into a projection that opposes the digits and grips a bamboo stem. The two lineages arrived at this independently, and in the red panda it may have originated for climbing before being applied to feeding.
The species is assessed as Endangered, with habitat loss and fragmentation across the eastern Himalaya as the principal pressures, compounded by poaching. Whether the red panda is one species or two, the Himalayan Ailurus fulgens and the Chinese Ailurus styani, is unsettled; genomic work supports a split that not all authorities accept, and the answer changes how conservation units are drawn.