Taxonomic revision of Thai Gnetum (Gnetaceae), including two new species
DOI:
https://doi.org/10.20531/tfb.2026.54.1.04Keywords:
Flora of Thailand, Gymnosperms, Gnetales, Lectotypes, Tropical plantsAbstract
A comprehensive taxonomic revision of Gnetum (Gnetaceae) in Thailand is presented based on morphological characters. Eleven taxa are recognised (ten species and two varieties) including two newly described species, Gnetum khaoluangense and G. megaspermum, both endemic to Thailand. An update of morphological characters, taxon descriptions (including illustrations of the two new species), diagnostic characters, and an identification key to all Thai taxa, are provided. Lectotypification is provided for six taxa: G. cuspidatum, G. gnemon var. tenerum, G. leptostachyum, G. macrostachyum, G. microcarpum and G. tenuifolium.
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