Preliminary Conservation Checklist of Orchid of Gashaka Gumti National Park, Nigeria

Abstract

A preliminary checklist of the Orchidaceae of Gashaka Gumti National Park (GGNP) is presented, based on previous reports on the flora of GGNP and recent botanical explorations. The results from this study recorded 80 orchid species in 38 genera. The collection consists of 84% epiphytes and 16% terrestrial orchids. The genera with highest number of species are the Bulbophyllum (16 species) and Polystachya (11 species), while Habenaria is the richest terrestrial genus with five species. Afropectinariella gabonensis, Bulbophyllum renkinianum and Rhipidoglossum polydactylum are newly recorded for Nigeria. Other noteworthy taxa include Angraecopsis elliptica, Bulbophyllum calvum, Holothrix aphyllaand Tridactyle tridentata which are some of the rarest orchid species in Nigeria. The highest species number was recorded in the lowland forest of the southern sector, particularly Kwano, with 42 species, followed by 29 species in the montane forest, five species in the savanna woodland, and four taxa in the lowland gallery forest. Our study identified recent transhumance to the enclave of the park (leading to grazing), and illegal logging of Pterocarpus erinaceous and Afzelia africana as the major noticeable threats to the continued existence of orchid species in GGNP. Therefore, further inventories with rigorous techniques such as the tree climbing technique are warranted for an exhaustive inventory and effective conservation of the orchid flora of GGNP.