An Overlooked Weed “Purpletop Vervain” Verbena incompta P. W. Michael (Verbenaceae) Forms a New Record to the Flora of India

Verbena incompta P. W. Michael (Verbenaceae) an invasive species from Brazil is reported here as a new record for the flora of India. This species was observed growing as weeds along agricultural fields in western Uttar Pradesh, India and profusely flowering and fruiting with high seed number. It is morphologically similar to V. brasiliensis Vell. and V. bonariensis L. but clearly distinct from the latter species in leaf and inflorescence characters. The present account provides detailed botanical description and comparative account between three allied species, namely Verbena incompta P.W. Michael, V. brasiliensis Vell. and V. bonariensis L. along with identification key. Weed risk assessment indicated V. incompta as a “serious weed” with high invasive potential.