Format: ORAL

Janeesha A.P. Santhosh Nampy

Department of Botany, University of Calicut, Kerala – 673635, India

The genus Henckelia Spreng. (Gesneriaceae, sub-family Didymocarpoideae) includes 82 species, distributed in Northeast and South India, Sri Lanka, Myanmar, Nepal, Bhutan, southern China, northern Vietnam, northern Laos and northern Thailand. The genus was treated earlier as a synonym of Didymocarpus Wall. until it was resurrected and remodeled by Weber and Burtt (1997). Weberet al. (2011) re-defined the genus based on molecular data and included species ofHenckeliasect.Henckelia,Chiritasect.Chirita (excluding the species underDamrongiaKerrexCraib), the monotypic genusHemiboeopsisW.T.Wang and exclude the species ofHenckeliasect.Loxocarpus,Didymanthus,HeteroboeaandGlossadenia. Henckelia includes mainly perennial plants, sometimes with a woody base; caulescent to acualescent (rarely creeping) habits; infundibuliform to tubular corolla; geniculate or straight filaments; unilocular or bilocular ovary; chiritoid to (rarely) truncate stigma and capsules splitting into 2 valves, or only along the dorsal side. Species of Henckelia generally fall under two groups: (1) plants predominantly caulescent, with internodes and leaves in whorls of 2 or 3, and orthocarpic capsules dehiscing along both upper and lower suture; (2) plants predominantly acaulescent, with leaves in basal rosette and plagiocarpic capsules opening along the upper suture only. The former group includes 64 species, distributed throughout the distributional range of the genus except South India, while the latter group includes 18 species, found in South India as well as in Sri Lanka. All the 16 species of Henkelia found in South India are acualescent, whereas Sri Lanka has eight species of Henckelia of which three are acaulescent. Henckelia humboldtiana (Gardner) A.Weber & B.L.Burtt is the acaulescent species seen both in South India and Sri Lanka. The present paper discusses the taxonomy, ecology and endemism of the acaulescent Henckelia. A phylogenetic tree is also constructed from ITS and trn loci.