A New Lopholejeunea (Spruce) Schiffn. (Hepaticae:Lejeuneaceae) from India

The genus Lopholejeunea (Spruce) Schiffn. is globally represented by 30 species referable to three subgenera viz., subgenus Pholianthus B.M. Thiers & Gradst. (with a single species confined to Australia and New Zealand), subgenus Pteryganthus B.M. Thiers (with four species confined to East Africa) and subgenus Lopholejeunea (with 25 species distributed all over the tropics, 17 of which occur in Asia) (Zhu & Gradstein, 2005). In India Awasthi & al. (2000) and Singh & Nath (2004) recorded 11 species and two varieties distributed in Eastern Himalaya (8 taxa), Western Ghats (7 taxa), Western Himalaya, Central India and the Andaman & Nicobar Islands (one species each). However, Zhu and Gradstein (2005), who further grouped the Asiatic species of the subgenus Lopholejeunea into sections Lopholejeunea (with 9 species characterized by the apex of leaf lobule attached to the leaf lobe across 2-8 cells) and Eulophae Verd. (with 8 species characterized by the leaf lobule attached to the leaf lobe across a single cell), recognised only 5 species from the country viz., L. applanata (Reinw. & al.) Schiffn., L. eulopha (Taylor) Schiffh. [=L. nicobarica Steph.] and L. nigricans (Lindenb.) Schiffh. [=L. abortiva (Mitt.) Steph. var. abortiva, L. abortiva var. doliiformis U.S. Awasthi & al., L. javanica (Nees) Schiffn., L. kashyapii U.S. Awasthi & al., L. sikkimensis Steph. var. dentata U.S. Awasthi & al., L. sikkimensis Steph. var. sikkimensis] belonging to sect. Eulophae, and L. recurvata Mizut. and L. subfusca (Nees) Steph. [=L. nilgiriensis U.S. Awasthi & al. and L. indica Udar & U.S. Awasthi] belonging to sect. Lopholejeunea. Later S.K. Singh & D.K. Singh (2006) described a new variety, L. sikkimensis var. tenuicostata Sushil K.Singh & D.K. Singh from the Western Himalaya, whereas Singh and Nath (2006) described L. nongstoinii A.P.Singh & V. Nath from the Eastern Himalaya.

During recent studies on the epiphyllous liverworts of Eastern Himalaya, an interesting population of the genus, referable to sect. Lopholejeunea, was observed in West Siang district of Arunachal Pradesh, which on the basis of comparative evaluation of morphological characters of species hitherto known under this section merit the status of a new species.