Ceropegia odorata Hook. f. (Asclepiadaceae): A Little-Known Plant of Western India

Abstract

Ceropegia odorata Hook. f. (Asclepiadaceae) is one of the little-known plants of western India. It was described by J. D. Hooker (1883) in the 'Flora of British India' based on material collected by Stocks & Law from 'ConcanSalsette' and deposited in the Kew Herbarium. Surprisingly Cooke (1904) does not list it in his 'Flora of the Bombay Presidency'; Huber (1958) in his treatment of the genus Ceropegia remarks 'In peninsula Indiae Orientalis in parte occidentali' citing the same collections and localities. All the subsequent workers on the flora of Bombay including Santapau and Irani, who have monographed the Asclepiadaceae and Periplocaceae of Bombay have included the plant in their works based solely on the above mentioned collections at Kew. According to D. V. Field (Royal Botanic Gardens, Kew), 'the specimens in the Kew Herbarium are two Stocks & Law (coll. Law) as well as a Dalzell collection from Bombay'. It is, therefore, evident that the plant is endemic to western India and that it is a very rare plant, which has never been observed or collected since the century-old collections made by Stocks, Law and Dalzell. The name Ceropegia odorata has been a subject of some discussion. It first appeared, under the authorship of Nimmo, in Graham's 'Catalogue of Bombay Plants' (1839) accompanied by an incomplete and vague description 'Flowers yellow, fragrant; so unusual in this genus', which cannot be considered diagnostic. The Stocks & Law specimens at Kew have 'MSS.' written after the name Ceropegia odorata Nimmo. Hence the name Ceropegia odorata Nimmo becomes a nomen subnudum, as pointed out by Huber (1958), and is not validly published. Hooker provided an ample diagnosis of the plant but according to Santapau (i948) 'there are no specimens in the Hooker Herbarium preserved at Kew which have been identified by Nimmo. Strictly speaking then, what Hooker actually did was to describe a new plant of his own, which he could have named as he pleased, but which he named C. odorata Nimmo on the assumption that both plants were identical. Hooker, however, has not proved such an identity'. McCann (1945) renamed Hooker's plant as C. blatteri McCann, which according to Huber (1958) was unnecessary. In his opinion (Huber) 'Nimmo's name belongs to a different species, but this has yet to be proved although the chances of doing so are slender'. Ceropegia odorata Hook. f. is a very rare endemic, and a record of its occurrence in the Panchamahal District of Gujarat State is of special interest. The plant has been re-collected after a lapse of more than I oo years at a place far removed from the type-locality.