Takahashi, R. 1955 Protopulvinaria and Luzulaspis of Japan (Coccidae, Homoptera).. Annotationes Zoologicae Japonenses. Tokyo 28: 35-39.

Notes: Key to Protopulvinaria (3 species); P. japonica = P. [L.] fukayai (Kuw.); P. agalmae = P. pyriformis (Ckll.); Luzulaspis caricus n. sp.