Table 3 in Genus-level revision of the Alycaeidae (Gastropoda, Cyclophoroidea), with an annotated species catalogue

Table 3. Important traits of Alycaeid genera. GenusProtoconch sculptureTube (R2) lengthShell diameter (mm)Central toothKey traitUnclear relationship withAlycaeussmooth to obliquely striatedvery long (ca. 1/2 whorl)8-155 cusps, broad, central cusp bluntshell very large, R2 ca. half whorl longPincernaChamalycaeussmooth, usually elevatedvariable2-55 cusps, broad, central cusp pointedshell very small to medium sized, usually depressed, R2 of variable lengthPincernaDicharaxsmooth, usually lowvariable1-115-7 cusps, broad, central cusp pointedprotoconch + teleoconch without spiral striaeDioryxsmoothvariable3.5-95-7 cusps, broad, central cusp bluntshell globular or high-spired, sculpture reduced, R3 absentMetalycaeusspirally striated, elevatedvariable3-105 cusps, broad, central cusp pointedprotoconch spirally striatedPincernasmoothvery short to short2.5-65 cusps, broad, central cusp pointedshell very small to medium sized, high spired, R2 shortAlycaeus, Chamalycaeus, StomacosmethisStomacosmethissmoothvery short3-13elongated, usually with 1 central cusp only, or central cusps with 1-2 small cusp at each sidetiangular, colourful shell, R2 very shortPincerna