Two New Species and Two New Records of Marsdenia (Apocynaceae) From Thailand

Two new species, Marsdenia thailandica Rodda and M. epedunculata Rodda are described and illustrated. The former is characterised by large flowers ca. 15 mm in diameter and prominent calyx lobes longer than the corolla tube, while the latter by globose, epedunculate inflorescences. Marsdenia cavaleriei and M. jenkinsii are new records for the flora of Thailand. A lectotype is designated for the name M. jenkinsii Hook. f.