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Genus Corythion

In ventral view, the shell is ovoid; in lateral view the shell is compressed; cross-section lenticular lateral margins often slightly acute. Shell is covered by on type of body plates: circular, rectangular, imbricated, irregularly distributed but at lateral margins in rows. Aperture is invaginated, oval, semicircular or circular, surrounded by plates with one central tooth. Some species have short organic or siliceous spines. Type species: Corythion dubium Tarànek, 1881