Zaptyx, PILSBRY, 1900

Motochin, Risho, Wang, Min & Ueshima, Rei, 2017, Molecular phylogeny, frequent parallel evolution and new system of Japanese clausiliid land snails (Gastropoda: Stylommatophora), Zoological Journal of the Linnean Society 181, pp. 795-845 : 834

SUBGENUS ZAPTYX PILSBRY, 1900

(= SUBCLADE D8)

Synonyms: Metazaptyx Pilsbry, 1905 ; Diceratoptyx Pilsbry, 1905 ; Idiozaptyx Pilsbry, 1909 .

Diagnosis: Shell small, slender. Superior lamella usually developed, rarely reduced. Inferior lamella variable, spirally ascending and appearing at the aperture, or almost straightly ascending and receded within the aperture. Sutural plica always present, one or two. Lunella present, usually developed, rarely shortened in an exceptional case. Upper palatal plica present, usually short, rarely long and/or interrupted. Lower palatal plica usually absent. Clausilium wide or narrow. Reproduction oviparous or ovoviviparous. Distribution: endemic to the Ryukyu Islands and southern Kyushu.

Morphology: Apex pointed. Plicae and clausilium located laterally. Principal plica developed. Middle palatal plica absent. Diverticulum of bursa copulatrix developed. See also Diagnosis.