Campascus dentatus Edmondson and Kingman, 1913
Diagnosis: Shell of yellowish, chitinoid material similar in general outline to C. cornutus. Under high magnification, the shell has the appearance of being distinctly punctate. In some individuals the punctae are arranged in a regular diagonal manner, in others there is no regularity about the arrangement. In no specimens examined can outlines of plates be detected even with an oil-immersion lens. The neck is short and sharply bent, nearly at right angles to the long axis of the shell. The circular aperture is bordered by a thin delicate membrane of approximately 4 µm breadth. A number of short, blunt, tooth-like prolongations are present on the posterior border of the fundus. From three to seven of these processes are usually present. They vary in size and when numerous give an irregular, crenulated appearance to the posterior edge of the fundus, when the broad side of the shell is viewed.
Dimensions: Length including spines and collar: 60-80 µm; width of the fundus 50-66 µm.
Ecology: Ooze on rocks along the shore of Lake Hakone, Japan, 1912.