The genus <i>Commelina</i> (Commelinaceae) in Andaman & Nicobar Islands, India with one new species and three new records

Abstract

A synopsis of the genus Commelina in Andaman and Nicobar Islands is presented with one new species and three new records. The new species, C. andamanica is remarkable by its trailing habit without a definite base, solitary and terminal, cucullate spathe with a single cincinnus and two smooth seeds within a capsule. Of the seven species of Commelina recorded, C. attenuata, C. clavata and C. longifolia are new to the islands. An identification key to all the species reported from Andaman and Nicobar Islands is also provided.

Synopsis of Commelina L. (Commelinaceae) in the state of Rio de Janeiro, reveals a new white-flowered species endemic to Brazil

“…On the other hand, most of the morphological characters pointed out by previous authors ( e.g. Faden 1993, 2008; Nampy et al 2013) as key to the taxonomy of the genus are mostly difficult to observe in herbaria specimens. Thus, work to expand and refine the morphological tools available to workers in this group should be ongoing.…”

“…This genus in particular poses problems as floral characters are difficult to observe in dried specimens ( e.g. Faden 1993, 2008, 2012; Nampy et al 2013), which calls for particular attention to be paid to adequate description of these in any new species (Faden 2008). Historically there are examples where either floral, fruit, or seed characters are only incompletely described, or even omitted.…”

Commelina littoralis (Commelinaceae), a new species from India

“…One of the Indian archipelagos, the Andaman and Nicobar Islands has a coastline with stunted evergreen tropical rainforests, and mangrove and littoral forest habitats which harbours some exclusive Commelinaceae taxa, viz. Murdannia sanjappae M.C.Naik & B.R.P.Rao (Naik and Rao 2017), M. saddlepeakensis Ramana & Nandikar (Ramana et al 2013), C. andamanica S.M.Joseph & Nampy (Nampy et al 2013). One subspecies M. crocea subsp.…”

Commelina badamica (Commelinaceae), a new species from India

“…Most of the species occur as weeds along roadsides or in cultivation fields, but a few of them are restricted or exclusively known from forest habitats (Faden 2012;Nandikar 2013Nandikar , 2014. In India, the genus is represented by 25 species (Nampy et al 2013) of which Commelina alisagarensis Kumar & Deodikar (1941), C. hirsuta (Wight) Bedd. (Beddome 1880), and C. tricolor E. Barnes (1946) are apparently endemic.…”

“…(Beddome 1880), and C. tricolor E. Barnes (1946) are apparently endemic. Recently, two new species Commelina clavatoides Nampy & S.M.Joseph (Joseph et al 2012) and C. andamanica S.M.Joseph & Nampy (Nampy et al 2013) have been added to the Indian flora. However, the distinctiveness of the former species from C. clavata C.B.Clarke (1874) requires further study.…”