Murdannia assamica Nampy & A.Ancy, a new species of Murdannia (Commelinaceae) from India, is described and illustrated. It is similar to Murdannia nudiflora but differs in the cincinnus, antherode, capsule and seed characters.

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.

The genus Swertia in South India is revisited based on field and herbarium studies. A brief history of the genus, detailed descriptions, photo plates, nomenclature, distribution and key to the identification of south Indian species are provided. Seven names viz., Swertia beddomei, S. trichotoma, S. affinis, S. lawii, S. minor, Ophelia elegans and O. umbellata are lectotypified. A new species, Swertia raveendrae, endemic to South India is also described here. The new species is similar to S. lawii but differs by its cordate-orbicular leaves, dense paniculate cymes, small (0.3–1 cm long), ovate-elliptic bracts and the calyx not exceeding the corolla in bud.

Murdannia nudiflora (L.) Brenan is a day flower that is dependent on entomophilous pollination. Despite the lack of pollinator attractants and its short flower longevity, M. nudiflora shows high rates of fecundity, which lead to their rapid dispersal. In addition to monitoring the vegetative reproductive methods and the effect of select environmental parameters (atmospheric temperature, relative humidity, and precipitation rates) in M. nudiflora, we evaluated mating systems in this species via artificial crosses. This species has evolved to undergo autogamy to ensure reproductive success when pollinators are insufficient; cleistogamous flowers are produced for optimal pollinator activity when environmental conditions are unfavorable. The number of cleistogamous flowers produced was found to be positively correlated with humidity and precipitation rates, and negatively correlated with temperature. In addition, it was found that high humidity and precipitation always hinder insect pollinators. Therefore, the combination of vegetative reproduction, entomophily, and cleistogamous self-pollination helps this weedy species to propagate with maximum efficiency. Murdannia nudiflora employs pre-anthesis cleistogamy as a mating strategy for reproductive assurance while retaining mechanisms that promote out-crossing.

Impatiens stolonifera, a new scapigerous species of Balsaminaceae from the southern Western Ghats, is described and illustrated. The new species is morphologically allied to Impatiens scapiflora, but differs by having a stoloniferous tuber and white flowers with conspicuously long and broad spur.

No abstract

No abstract

No abstract