The conservation status of Diaphanoptera stenocalycina (Caryophyllaceae), a rare endemic species in Iran

Diaphanoptera stenocalycina Rech. f. & Schiman-Czeika is a cushion form species of the Caryophyllaceae family. This species is endemic and known from Mirzabailu plain (in the eastern part of Golestan National Park) and its neighboring area in the west of North Khorasan Province. In the present study, the conservation status of the species was assessed based on the IUCN criteria and categories, including the area of occupancy (AOO), the extent of occurrence (EOO), and the size of populations. Based on these data, the values of AOO and EOO are about 1.5 and 164.078 square kilometers, respectively. Accordingly, the conservation status of the species is classified as critically endangered (CR). The small population, low regeneration rate, and low precipitation are the main factors threatening the species. It is recommended that the conservation programs should consider both wildlife and plant species. Considering the rarity of the species, conserving the seeds in the National Natural Resources Seed Bank and cultivating them in botanical gardens is suggested.