CLAUSILIIDAE GRAY, 1855

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 : 822-825

FAMILY CLAUSILIIDAE GRAY, 1855

SUBFAMILY PHAEDUSINAE WAGNER, 1922 GENUS STEREOPHAEDUSA BOETTGER, 1877

(= CLADE A)

Type species: Clausilia valida Pfeiffer, 1850

Synonyms: Breviphaedusa Azuma, 1982; L u ch u p h a e d u s a P i l s b r y, 1 9 0 1; M e s o p h a e d u s a Ehrmann, 1929; Nesiophaedusa Pilsbry, 1905 ; Oophaedusa Pilsbry, 1905 ; Pliciphaedusa Nordsieck, 1998 ; Vastina Ehrmann, 1929 .

Diagnosis: Although, Stereophaedusa redefined here cannot be diagnosed by morphology, its monophyly is strongly supported by molecular phylogeny. The presence of unique deletions and substitutions in the hyper variable region of ITS2 ( Fig. 5) is a molecular diagnostic character of the genus.

Morphology: Shell small to large. Apex usually pointed and preserved, rarely decollated in adult. Plicae and clausilium located laterally to ventrally. Superior lamella always developed. Inferior lamella variable, spirally or obliquely ascending and appearing at the aperture, or almost straightly ascending and receding within the aperture. Lunella present or absent. Principal plica developed. Middle palatal plica(e) present or absent, rarely coalesced into a lunella. Clausilium wide or narrow. Diverticulum of bursa copulatrix developed.