Wondiwoi tree-kangaroo

It was named in honour of Ernst Mayr, who collected the type specimen now deposited in the Natural History Museum, London.[2] It was described by Lord Rothschild and Capt. Guy Dollman in a 1933 paper[5] and an illustration based on the only known specimen was published in their 1936 monograph on the genus.[6]

In July 2018,[7] what may prove to be the first ever photographs of the species were taken by British naturalist Michael Smith.[8][9] Smith was investigating Vireya rhododendrons in an unexplored area of the Wondiwoi ranges and photographed a 'dorianus type' tree kangaroo at an altitude of approximately 1,600 metres. Scent marks, tree kangaroo scat and claw marks at the base of trees made by climbing tree kangaroos were found from 1,700m to 2,000m in steep montane forest. Local hunters, who frequently kill Grizzled tree kangaroos in lowland forest, rarely if ever visit the forest above 1,500m because of the difficult terrain, lack of water sources and dense bamboo thickets.

Long thought to be extinct or critically endangered,[10] the IUCN Red List listed the species as Critically Endangered (Possibly Extinct) because "if the species still exists the population must be very small (less than 50 mature individuals) and probably in decline due to hunting pressures. Although the area has not been well-sampled, there have been a few visits to the area with no reports of this species."[11] In 2018, a British amateur botanist photographed what is believed to be a living specimen of the Wondiwoi tree-kangaroo in the mountains of New Guinea.[12]

The species status of Dendrolagus mayri is uncertain. Some authorities refer to all 'dorianus type' tree kangaroos as subspecies of Doria's tree kangaroo, including Colin Groves, who published a major revision of the taxonomy of the genus in 1982.[13] More recent DNA analysis indicates, however, that the members of the dorianus group deserve species status, although Dendrolagus mayri itself was not included in the study.[14]