Panisea panchaseensis sp. nov. (Orchidaceae) from central Nepal

Abstract

Panisea panchaseensis Subedi sp. nov. (Orchidaceae) is described as a new species from Nepal. The distinguishing characters, a description, detailed illustrations and photographs are provided. The species is genetically compared to P. tricallosa, and a diagnostic key based on the morphology to all species of Panisea is provided. The genus Panisea (Lindl.) Lindl. (Orchidaceae, Epidendroideae, Coelogyninae) consists of 10 species (Lindley 1830, 1854, Chen 1980, Lund 1987, Gravendeel et al. 2005, Averyanov and Averyanova 2006). These species are distributed from the Indian subcontinent to southeast Asia. The genus is easily recognized by the pseudobulbs consisting of a single internode, convolute or duplicate leaves, terminal inflorescence often produced before growth of the pseudobulbs, resupinate flowers, lip with more or less sigmoidly curved base with completely absent or only small side lobes (this character is its main diagnostic feature within the Coelogyninae), a ‘petaloid’ apex of the column hooded over the anther, and entire stigma. In 2002, the first author came across an interesting specimen of Panisea which was collected from Panchase forest in central Nepal. This species was found in the same habitat zone where Panisea demissa Lindl. commonly occurs. The specimens looked very different in habit and flower morphology compared with P. demissa. However, due to limited flowering material, it was impossible to properly investigate their taxonomic identity. In 2007, additional explorations were carried out in the same area and more flowering specimens were located. A study of herbarium specimens of similar species of Panisea, a detailed literature review and DNA sequencing were carried out to investigate whether the specimens from Panchase forest represented an undescribed species.