Synoptic account on angiosperm flora of Pudukkottai district, Tamil Nadu, India

Floristic composition was investigated during 2012–2022 from protected, unprotected forests patches of Pudukkottai district, Tamil Nadu, India. A total of 825 species belonging to 493 genera spreading over 117 families under 40 orders of vascular plants were listed during the study period. In terms of habit, the herbaceous species dominated (65%) other life forms such as shrubs, trees, and lianas (24%) and climbers (11%). The family Fabaceae (96) is the dominant one in the study area followed by Poaceae (93), Cyperaceae (49), Acanthaceae (36), Malvaceae (34), Apocynaceae (30), Euphorbiaceae (25), Asteraceae (25), Lamiaceae (24), Rubiaceae (23), and Amaranthaceae (20), that are account for 55% of the entire flora. The genera Cyperus L. (23) and Fimbristylis Vahl (16) are the widespread genera in the study area. Based on the Angiosperm Phylogenic Group IV classification, eudicots represent 73% of species, the monocots represent 26% of species and Basal angiosperms represent very least number of species (1%). More than forty-five endemic species confined to India are reported from the distrcit, of which Jasminum greenii Soosairaj & P. Raja, Derris gamblei Soosairaj, P.Raja & Dhatchan and Justicia tamilnadensis P.Raja & Soosairaj are strictly endemic to Pudukkottai district. Among 825 species of 270 species are included under different IUCN categories. The results of this study will help taxonomists, ecologists, and conservationists to maintain and improve the existing state of the vegetation for future generations. This study provides the baseline to simplify the establishment plan and proper approach for the management and conservation of plants in Pudukkottai district of Tamil Nadu.