in Sri Lanka - Ministry of Environment

Floristic richness in Sri Lanka is significantly high in the lowland regions compared to the otherparts of the country. Even within the wet zone, the distribution of indigenous floristic elementsshows remarkable localization and one quarter of the angiosperm flora of Sri Lanka is endemicand also concentrated in the perhumid southwest of the island (Gunatilleke and Gunatilleke,1990).Floristic elements in the lowland wet zone of Sri Lanka are relic and primeval in origin. Theirorigin dates back to the Deccan plate and shares Gondwana-Deccan ancestry and are, byfar, the most species-rich biome in the whole of south Asia (Gunatilleke and Ashton, 1987a).Remnants of these Deccan flora are now restricted to the fragments of lowland wet zone in SriLanka and the south west region of India, and important in revealing biogeographic history ofSouth Asia.Prominent plant taxaDipterocarpus community and the Mesua-Shorea (Doona) community are the two prominentfloristic comminutes in Sri Lankan lowland wet zone forests that comprise of dominant lowlandwet zone flora. In addition to that, lowland wet zone flora also exists in Campnosperma andother species community and Vitex-Dillenia-Chaetocarpus-Anisophylla community, especiallyin the early successional secondary forests (de Rosayro, 1942; Gunatilleke and Ashton,1987b). Dominant plant species of these floristic communities are listed in the table below.Dominant plant species of the different floristic communities in lowland wet zone forestsin Sri Lanka (de Rosayro, 1942; Gunatilleke and Ashton, 1987b).Floristic communityDipterocarpus communityMesua-Shorea (Doona)communityCampnosperma andother species communityVitex-Dillenia-Chaetocarpus-Anisophylla communityDominant plant speciesDipterocarpus zeylanicus, Dipterocarpus hispidus, Vitex pinnata,Chaetocarpus castanocarpus, Dillenia retusa, Dillenia triquetra,Myristica dactyloides, Semecarpus gardneriMesua ferrea, Mesua thwaitesii, Shorea trapezifolia, Shorea zeylanica,Chaetocarpus castanocarpus, Palaquium petiolare, Mangiferazeylanica, Myristica dactyloides, Garcinia echinocarpa, Agrostistachyscoriacea, Lasianthus strigosus, Aporusa lindleyana, HumboldtialaurifoliaCampnosperma zeylanica, Chaetocarpus castanocarpus, Palaquiumpetiolare, Myristica dactyloides, Dillenia triquetra, Gaertnera vaginans,Schumacheria castanaefolia, Thottea siliquosa, Syzygium neesianum,Vitex pinnata, Dillenia triquetra, Chaetocarpus castanocarpus,Anisophyllea cinnamomoides, Dillenia retusa, Myristica dactyloides,Semecarpus gardneri, Gyrinops walla, Cullenia spp., Mangiferazeylanica, Ochna wightiana, Xylopia championii, Garciniaechinocarpa, Diospyros insignis, Gaertnera vaginans, Thotteasiliquosa Schumacheria castanaefolia, Humboldtia laurifolia, Syzygiumcorymbosum, Symplocos spicataDipterocarpaceae, Clusiaceae, Myrtaceae, Bombacaceae, Dilleniaceae, Euphorbiaceae andSapotaceae are the dominant plant families in lowland wet zone of Sri Lanka.176