Arctic reindeer
The Arctic reindeer, properly known as the East Greenland caribou, was a subspecies of the reindeer that once lived in eastern Greenland. It has been extinct since 1900.
Archaeologists have found bones of small caribou the size of Peary caribou, Rangifer arcticus pearyi, throughout Greenland in the Illinoian-Wisconsin interglacial and through the LGM and early Holocene. Degerbøl described the East Greenland caribou, R. t. eogroenlandicus, a small caribou that became extinct about 1900, from a relict enclave in north-eastern Greenland. However, Anderson thought that the small caribou that were occasionally found in northwest Greenland were Peary caribou. Bennike, comparing bones and noting that Peary caribou have been documented crossing Nares Strait to Greenland, doubted that pearyi and eogroenlandicus were subspecifically distinct. That Peary caribou shared certain mtDNA haplotypes and morphological similarities with it casts further doubt on the validity of R. t. eogroenlandicus. Inuit Qaujimajatuqangit records that Peary caribou do, occasionally, cross to Greenland.
The Greenland caribou or reindeer is larger and darker and not referable to either R. a. pearyi or R. t. eogroenlandicus.