Investigation on the Cycadales of Eastern Ghats and North East India

Abstract

It deals with the taxonomy, geographical distribution, population and conservation status and ethnoecology of the cycad of the Eastern Ghats and North Eastern states of India. Perusal of literature revealed the confusion related to the geographical distribution and taxonomy of Cycas circinalis var. orixensis Haines, C. sphaerica Roxb. C. circinalis in the Eastern Ghats and C. pectinata Ham. in the Northeastern states of India. It was felt therefore, to survey and explore the cycad populations of these two geographical regions to inquire two main hypotheses: newline newlinea) What is the geographical range of C. circinalis L.? Whether it is restricted to Southern Western Ghats or does it extend up to the Northern Eastern Ghats? newlineb) Whether C. pectinata of North East Indian states is a single species or a complex of cryptic taxa? newline newlineSeveral objectives were undertaken to comprehensively investigate these research questions: newlineThe present study has resulted into some important contributions that would be helpful in deciphering the taxonomy of the Indian Cycadales. newline newline1) Three new species of Cycas: C. orixensis, C. nayagarhensis and C. kalingana are newlinediscovered from Odisha in the Northern Eastern Ghats of India which are new to newlinethe science. newline2) Taxonomical assessment suggests that the Cycads of Northern Eastern Ghats are newlinedistinct from C. circinalis L. and C. sphaerica Roxb. and thus can not be synonymised under C. sphaerica Roxb. as suggested by Lindstrom and Hill(2007) newlineor cannot be treated as a variety of C. circinalis (Haines, 1924) newline3) These newly described taxa are endemic to the Northern Eastern Ghats of India newlineand have reproductive features hitherto unknown in any Cycas species of the newlineworld. A new Subsection Orixenses has thus been created within the Section newlineCycas to include the C. orixensis, C. nayagarhensis and C. kalingana. newline4) A revised Infrageneric classification of the Genus Cycas (Hill 1995) is proposed newlinehere after inclusion of the Subsection Orixenses in the Section Cycas. newline5) On the basis of comprehensive and taxonomic .....