Protophyllum pterospermifolium Lesquereux, 1891 species accepted

Quercus mudgii (Lesquereux, 1871) species accepted

Credneria leconteana (Lesquereux, 1868) species accepted

Protophyllum dimorphum Lesquereux, 1891 species accepted

Protophyllum undulatum Lesquereux, 1891 species accepted

Pterospermites quadratus (Lesquereux, 1871) species accepted

Pterospermites haydenii (Lesquereux, 1871) species accepted

Protophyllum boreale Dawson, 1882 species accepted

Protophyllum praestans Lesquereux, 1891 species accepted

Protophyllum nebrascense Lesquereux, 1874 species accepted

Pterospermites multinervis (Lesquereux, 1871) species accepted

Pterospermites rugosus (Lesquereux, 1872) species accepted

Protophyllum crenatum Knowlton, 1891 species accepted

Protophyllum pseudospermoides Lesquereux, 1891 species accepted

Protophyllum nanaimo Dawson, 1882 species accepted

Protophyllum haydenii (Lesquereux, 1871) species synonym

Protophyllum mudgii (Lesquereux, 1871) species synonym

Protophyllum quadratum (Lesquereux, 1871) species synonym

Protophyllum leconteanum (Lesquereux, 1868) species synonym

Protophyllum denticulatum Lesquereux, 1891 species accepted

Protophyllum multinerve (Lesquereux, 1871) species synonym

Protophyllum rugosum (Lesquereux, 1872) species synonym

Protophyllum querciforme Hollick, 1895 species accepted

Protophyllum crednerioides Lesquereux, 1874 species accepted

Protophyllum minus Lesquereux, 1874 species accepted

Protophyllum integerrimum Lesquereux, 1891 species accepted

Protophyllum obovatum Newberry, 1895 species accepted

Protophyllum sternbergii (Lesquereux, 1872) species accepted

Protophyllum crassum Lesquereux, 1891 species accepted

Protophyllum semotum Hickey, 1977 species accepted