Nice and informative. Keep up the good work. Best wishes for the week. Regards Pankaj
On Mon, Feb 7, 2011 at 10:20 AM, Mayur Nandikar <[email protected]> wrote: > Very special Commelinaceae morning to all.................. > FEW WORDS ABOUT COMMELINACE > > Spiderworts, the members of family Commelinaceae, are widely distributed > throughout the world, however, in spite of their vegetative propagation > species are sparsely distributed and many of them are endemic. The three > major centers of taxonomic diversity of Commelinaceae are: Tropical Africa; > Mexico and Northern Central America; and the Indian subcontinent. In the > family only six genera (Aneilema, Buforrestia, Commelina, Floscopa, > Murdannia and Pollia) have indigenous species in both the New World and the > Old World (Faden, 1978). > > Family Commelinaceae comprises about 41 genera and 650 species distributed > mostly in the tropical and warm temperate regions of the world (Faden, > 2000). According to Faden (1998a) Peninsular India and the foothills of > Himalayas to Thailand and Southwestern China is major center of diversity > for Commelinaceae. It is represented in India with 14 genera and 85 species > (Karthikeyan and Jain, 1989). > > Systematic Position: > > The family Commelinaceae is very natural and mostly very well defined. Its > characters and relationship with other families belonging to Farinosae have > been fully discussed by Hamann (1961, 1962 and 1963). Bruckner (1926) > classified the family in two subfamilies- Tradescantieae with actinomorphic > and Commelineae with zygomorphic flowers. Tradescantieae is further divided > into ‘Declinatae’ and ‘Inclinatae’ determined by floral buds being bent away > and towards the axis respectively. The genera Murdannia Royle are separated > from Aneilema R. Br. on the basis of floral symmetry (Bruckner, 1926). > According to him Aneilema in the restricted sense belongs to sub family > Commelineae, whereas Murdannia to Tradescantieae. Woodson (1942) also > recognized two tribes in Commelinaceae viz. Tradescantieae and Commelineae; > the former has paired sessile scorpoid cymes which appear as two sided units > superficially, whereas in the later ultimate branches of inflorescence of > individual scorpoid cymes appear one sided. Supposedly he rejected the idea > of sorting out Murdannia from Aneilema and kept them in his tribe > Commelineae. > > Bentham and Hooker (1883) put the Family Commelinaceae in the > series ‘Coronariae’ along with the families Roxburghiaceae, Liliaceae, > Pontenderiaceae, Philydraceae, Xyridaceae, Mayaceae and Rapataceae. Engler > (1895 and 1897) and Rendle (1904) placed the family in order ‘Farinosae’ > under sub-order ‘Commelinae’ consisting single family Commelinaceae. Order > Farinosae of Engler and Prantle (1915) also includes Flagellariaceae, > Restionaceae, Centrolepidaceae, Mayaceae, Xyridaceae, Eriocaulaceae and > Philydraceae; and is characterized by copious mealy endosperm. Bessey (1915) > placed the family in his order ’Liliales’, which include Liliaceae and > Najadaceae, along with many families of Farinosae of Engler. According to > Hutchinson (1934) his order Commelinales including Commelinaceae, Mayaceae, > Flagellariaceae and Cartonemataceae to be a basic terrestrial stock of his > Calyciflorae, from which has evolved his order Zingiberales. The seeds of > the members of Commelinales are characterized by having an ‘embryotega’, a > special development of micropyle (Hutchinson, loc. cit.). > > The predominant trend, which begun by Meisner (1842), was to > divide the family into two major groups. His tribe Tradescantieae had 6 > fertile stamens while tribe Commelineae had a reduced number of fertile > stamens. Hasskarl (1870) used Meisner’s classification, as did Clarke > (1881), who also separated out a small, third tribe, Pollieae for genera > with berries or berrylike fruits. > > Bruckner (1926 and 1930) raised the two major divisions of the > family to subfamily rank and distinguished them on the basis of floral > symmetry- subfamily ‘Tradescantieae’ (flowers actinomorphic) and subfamily > ‘Commelineae’ (flowers zygomorphic). Subfamily Tradescanteae was divided > into tribes Hexandreae (6 fertile stamens) and Triandreae (3 fertile > stamens). Subfamily Commelineae was split into tribes Declinatae (buds bent > downward, the posterior stamens less developed and usually sterile) and > Inclinatae (buds curved inward, the 3 anterior stamens less developed and > usually sterile). > > Woodson (1942) and Rohweder (1956), focusing on the American > genera, returned to 2 tribes, Commelineae and Tradescantieae, but defined > them on the basis of inflorescence rather than floral characters. > > Pichon (1946) was the first worker to completely break away from > the tradition of dividing the family into 2 major components. He recognized > 10 tribes-Tradescantieae, Callisieae, Anthericopsideae, Commelineae, > Geogenantheae, Cochliostemateae, Pseudoparideae, Zebrineae, Cyanoteae and > Dichorisandreae, on the basis of morphological characters. He further > separated the genus Cartonema into its own family Cartonemataceae, based in > part, on anatomical grounds. > > Brenan (1966) recognized 15 informal ‘groups’, using a > combination of morphological characters. He predicted that not all of his > groups would prove to be of equal taxonomic rank. > > The history of the subdivision of the Commelinaceae was > summarized by Faden and Hunt (1991) (briefly previwed by Faden, 1985), > accepted 2 subfamilies- subfamily Cartonematoideae (tribes Cartonemeae and > Triceratelleae) and subfamily Commelinoideae (tribes Tradescantieae with 25 > genera and 285 species and Commelineae with 13 genera and 348 species). > Within the tribe Tradescantieae, 7 subtribes were accepted- Palisotinae, > Dichorisandrinae, Thyrsantheminae, Streptoliriinae, Cyanotinae, > Coleotrypinae and Tradescantiinae. > > Hereby I am attaching a image, represents diversity among the family > Commelinaceae in India. > > (Photograph credit: Mayur Nandikar, Pravin Kawale, Vivek Kale, Rajdeo Singh) > > -- > Mr. Mayur D. Nandikar, > Research Student, > Department of Botany, > Shivaji University, > Kolhapur. > -- *********************************************** "TAXONOMISTS GETTING EXTINCT AND SPECIES DATA DEFICIENT !!" Pankaj Kumar Ph.D. (Orchidaceae) Research Associate Greater Kailash Sacred Landscape Project Department of Habitat Ecology Wildlife Institute of India Post Box # 18 Dehradun - 248001, India
