Subgenus (Ischnoplax) P. P. Carpenter in W. H. Dall, 1879 [W. H. Dall, 1879]

(7-0-5-3-0-5-4-6-11-0-0-0-0)
Ref. Abbott, 1974 p 394
Kaas & Van Belle, 1980

papillosus (C. B. Adams, 1845)

(7-0-5-3-0-5-4-6-11-1-0-0-0)
Size 0.3"-0.5" long
Ref. Abbott, 1974 p 394

pectinatus G. B. Sowerby, 1832 [T]

(7-0-5-3-0-5-4-6-11-2-0-0-0)
Ref. Abbott, 1974 p 394 Kaas & Van Belle, 1980