We designate the lectotype of Ptilophyllum pachyrachis Oishi (1940), collected from the Upper Jurassic (Tithonian) to Lower Cretaceous (Berriasian) Ashidani Formation of the Tetori Group exposed in Mochiana, Ohno City, Fukui Prefecture, Central Japan. We further propose a reclassification of this species to the genus Pterophyllum. We found that Oishi's (1940) syntypes included one Ptilophyllum specimen that reflected Eurosinian-type vegetation, contrary to the widely accepted idea that typical Siberian-type vegetation flourished in the Tetori Group region during the Tithonian to Berriasian.