Psammosilene tunicoides, a new generic and species record for Thailand, is reported. The new record was discovered on a degraded
calcareous substrate mountain in the western part of Thailand near the Thai-Myanmar border. The species was previously reported
to be endemic to SW China. This occurrence in Thailand greatly extends the distribution of the species. A lectotype is designated here.
Keywords
degraded calcareous substrate mountain, Doi Hua Mot, insufficiently known genus, lectotypification, medicinal plant, monotypic genus, taxonomy, Umphang District.