The only record of Thesium in Malaysia was hitherto the Southern Chinese Thesium psilotoides Hance from medium altitudes of the Benguet and Bontoe Mountain Provinces in North Luzon, according to Merrill (Enum. Philip. Fl. Pl. 2, 1923, 115), occurring between 1200 and 1500 m. The same species has also been found in the Lesser Sunda Islands, Sumba Island, by C. N. A. de Voogd (E. Sumba, 300 m, limestone quarry, De Voogd 1873 (80, L), Dec. 1, 1934, plant pale green, fruit yellow, flower white). The Sumba specimens exactly match the Philippine specimens. Species like this one, with a very short calyx tube, look astonishingly like Halorrhagis, in habit, but possess 5-merous flowers, lack bulbous-based hairs, and show a peculiarly cartilaginous leaf apex.