A new Brachionidium (Orchidaceae: Pleurothallidinae) from the first botanical expedition to the Volcán Cacho Negro, Costa Rica

Abstract

A new species of Brachionidium from Costa Rica is described and illustrated. Brachionidium cornu-nigricum, from the Volcán Cacho Negro, a remote, previously unexplored location in Costa Rica, is most similar to B. filamentosum. It differs in the white sepals, short-acuminate sepals and petals up to 1 cm long, the triangular, unlobed lip, the oblong glabrous callus provided with two small basal lobes, and the eight pollinia.