---

 

---

Commelinaceae - Wikipedia, the free encyclopedia

FAMILY OF THE WEEK: COMMELINACEAE - indiantreepix | Google Groups

---

 

Commelinales and Zingiberales Week: Commelinaceae:  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 distributedand 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 Murdanniato 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 Aneilemaand 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.

---

As per efi thread:

Stamens antesepalous......................Murdannia
Stamens all anterior............................
Fruits sticky with hook-hairs....... ......Rhopalephora
Fruit indehiscent, berry like...............Pollia
Fruit dehiscent .................................Dictyospermum