Two new species of Monolophus (Zingiberaceae) from India M. Bhaumik 1,2 , T. Langhu 3 , S. Dey 3 , C. R. Deb 3 & N. S. Jamir 3 Summary. Two new species of Monolophus are described and illustrated from north east India. A key to the Indian species is provided for easy identification. Key Words. Caulokaempferia, Kaempferia. Introduction The genus Monolophus was first described by Wallich (1820, 1832) with two species, but for a long time it was treated under Caulokaempferia K. Larsen (1964), separated from Kaempferia L. by the distinct stem, spicate inflorescence and entire staminal crest. Recently the genus Monolophus was reinstated by Mood et al. (2014) with 22 new combinations. The genus is distributed from Eastern Himalaya to south east Asia with the centre of diversity in Thailand. There are two distinct groups, the yellow-flowered species distributed in Thailand and adjacent countries, the other non-yellow- flowered (purple, red-purple, pink and white) group are localised in Eastern Himalaya as well as north east India. Previously, the genus was represented in India by three species: M. linearis (Wall.) Wall., M. secundus (Wall.) Wall. and M. sikkimensis (King ex Baker) Veldkamp & Mood (Roy & Barbhuiya 2013). Recent plant exploration in west Siang district of Arunachal Pradesh (MB) and the Sirohoi hills of Manipur (SD) by the first and third authors collected two interesting species of Monolophus. The specimens were compared with the published literature (Baker 1890; Larsen 1964, 1973, 1996, 2002; Larsen & Smith 1972; Rao & Verma 1972; Smith 1994; Wu & Larsen 2000) and the herbaria: ASSAM, ARUN, BSHC, BSD, CAL and DD were consulted but no match with any of the described species of Monolophus was found. There- fore they are described and illustrated here as new species. A key to the Indian species of Monolophus is also provided for easy recognition of the taxa in India. Materials and Methods Intensive and extensive field surveys were undertaken periodically during various flowering and fruiting seasons in different habitats of the West Siang and East Siang district of Arunachal Pradesh, India, from 2010 – 2015 for Flora of west Siang project and c. 6600 specimens were collected. Similar survey work also undertaken in the Shiroy hills, Ukhrul district of Manipur state from 2013 – 2014, for the survey of Zingiberaceae plants in Manipur. Field observations including habit, habitat, flower colour, odour, distribution, frequency of occurrence, associated species and other features were noted. The plant speci- mens were tentatively identified in the field. The speci- mens were dried, poisoned and mounted following conventional methods. The herbarium specimens were described and illustrated, then critically studied and their identities confirmed by referring to various regional floras and many other recent, relevant monographs and revi- sions. The specimens were also compared with herbarium specimens available in ASSAM, ARUN, BSD, BSHC, CAL, DD and the State Forest Research Institute, Itanagar herbaria. The herbarium images available in virtual herbaria including E, K, P, PE and WU were also consulted. After consulting all relevant literature and herbaria, we concluded that these two Monolophus collec- tions do not match with any described species of the genus. Therefore, they are described and illustrated here. Monolophus arunachalensis Bhaumik, S. Dey & Langhu sp. nov. Type: India, Arunachal Pradesh, West Siang, Roying to Tirbin, 28°22.929 N 94°41.340 E, 320 – 630 m, 9 Sept. 2011, Bhaumik 27329 (holotype CAL!; isotype ARUN!). http://www.ipni.org/urn:lsid:ipni.org:names:60473798-2 Perennial herbs, rhizome short; pseudostem erect, leafy, 30 – 75 cm long, 4 – 7 mm diam. Leaves 7 – 13, subsessile, petiole 1 – 3 mm long, minutely hairy; blade semi-membranous, oblong to oblong-elliptic, 6 – 16 × Accepted for publication 9 February 2017. 1 Arunachal Pradesh Regional Centre, Botanical Survey of India, Senki view, Itanagar, India. e-mail: dr_manasb@yahoo.com 2 Industrial Section of Indian Museum, Botanical Survey of India, Kolkata, India. 3 Department of Botany, Nagaland University, Lumami, 798627, Zunheboto, Nagaland, India. KEW BULLETIN (2017) 72:6 DOI 10.1007/S12225-017-9687-4 ISSN: 0075-5974 (print) ISSN: 1874-933X (electronic) © The Board of Trustees of the Royal Botanic Gardens, Kew, 2017