Solanum sisymbriifolium Lam. (Solanaceae): a new invasive undershrub of the old-fields of northeastern Uttar Pradesh

Solanum sisymbriifolium Lam. (Solanaceae), an undershrub species, was first identified at an upland site in the suburb of Gorakhpur town during a broad survey on the distribution and abundance of grassland and old-field species of northeastern Uttar Pradesh. The species was first noticed in August 2012, and by the start of 2014 it showed a highly significant increase in its number and vegetal cover. Morphologically the species provides a spectacular plant body by virtue of numerous long orange-red spines found along the stem and leaves to the calyx, large white flowers with bright yellow anthers, and its red ripe fruits present for most of the year. The plant body is largely unpalatable and also resistant to grazers. The rapid spread of this species within a short span of about two years indicates the potential for this perennial shrub as a harsh invader of upland sites of the region. A brief account of habitat and population size along with a morphological description and line drawing is provided for easy identification of the species, which is not yet reported from Uttar Pradesh