Notes on the taxonomy, typification, extended distribution and red list assessment of Bulbophyllum nodosum — an endemic and endangered orchid from India

Abstract

ABSTRACT Bulbophyllum nodosum (Rolfe) J.J. Sm. [Orchidaceae-Epidendroideae-Malaxideae-Dendrobiinae], an Indian endemic species, discovered originally from the Western Ghats in Tamil Nadu and later from the Eastern Himalayas in Arunachal Pradesh, has been recorded from Sikkim Himalaya for the first time, thereby extending its distribution further in the Himalayan region. This species resembles with Bulbophyllum helenae (Kuntze) J.J. Sm. and the two can be easily confused due to morphological similarities. However, the characteristic swollen nodes in the rhizome and a long compact tube formed by the lateral sepals (by cohering along their upper and lower margins) make Bulbophyllum nodosum unique and distinct from B. helenae. Further, a lectotype has been designated for Bulbophyllum nodosum in the present communication from the available original materials of the name. The species has been assessed as “Endangered” by applying the IUCN guidelines. A detailed description, photographic illustration, and information on its phenology, habitat, distribution and threats have been provided for easy recognition and taking the necessary conservation action of this threatened species. Additionally, a photo-plate of Bulbophyllum helenae is also provided to help in identifying these two closely looking species.