Anastrophyllum plagiochiloides INOUE & GRADST. is newly described and illustrated. This species is characterized by 1) the flat or more or less convex leaves, 2) the strongly oblique leaf-insertion line on the dorsal side, and 3) the narrowly oblong leaf-shape with a narrowly rounded or subtruncate and sometimes bidentate apex. As these characters sharply isolate the species from any other known species of Anastrophyllum, the new subgenus Vanaea INOUE & GRADST. is established for this remarkable species.