A new species of Justicia L. (Acanthaceae) from Tamil Nadu, India

Justicia tamilnadensis P.Raja & Soosairaj, sp. nov., a new species from Tamil Nadu, India is described and illustrated here. It is closely allied to J. salsoloides T.Anderson. Justicia tamilnadensis P.Raja & Soosairaj, sp. nov. is a prostrate herb with a slender, purplish-green, glabrous and angled stem; elliptic-oblong, glabrous, subsessile leaves; corolla pubescent on throat within and subterete capsules with a white tomentum whereas J. salsoloides is a small undershrub with rigid, white, tomentose and terete stem; spathulate, or oblong-lanceolate, subglabrous, sessile leaves; corolla glabrous within and compressed capsules with a brown tomentum. The identification key of Justicia L. from Tamil Nadu, the conservation status (Critically Endangered), and distribution map of J. tamilnadensis P.Raja & Soosairaj, sp. nov. are also provided.