Neottia dihangensis

Neottia dihangensis is a species of critically endangered orchid endemic to Arunachal Pradesh in India.^[1][2][3]

This is a terrestrial autotrophic orchid that can grow up to 30 to 40 cm high with hairy roots. The stem below the leaves is yellowish-green. Leaves broadly ovate and grows 7 to 9 cm above the ground. Rachis - 8 to 12 cm long with dense hair. It had 12 to 27 green flowers that grows at the end of the inflorescence. Petals measure 0.3 to 0.5 mm and lanceolate The sub-obovate lip measured 8 to 9 mm long and 3 to 6 mm wide.

It can be differentiated by closely resembling species Neottia nanchuanica by relatively more flowers, smaller leaves, longer peduncle along with other features.^[2]

This orchid was discovered by Dr.M.Bhaumik in 2010 during a survey inside the Dihang-Dibang Biosphere Reserve . As of 2021, it was not found anywhere else.^[1][2]

This species was found at an altitude of 3600 meters at the edge of a partly dense bamboo forest floor that had Rhododendron and Abies trees. It was described along with the Neottia confusa species. It flowers in July.^[2][4]

This species is named after the Dihang-Dibang Biosphere Reserve where it was discovered and described in 2010.^[2]

When discovered in 2010 only one patch with 6 to 10 individuals were seen in the wild. Due to the smaller population size and single known location it was considered critically endangered. Some of the potential threats suggested during the IUCN assessment includes avalanches, landslides and climate change. As of 2021, no known conservation measures were taken up, however this species is listed in CITES Appendix-II ensuring restriction on trade and collection.^[1]