Plectopylis Benson, 1860

Páll-Gergely, Barna, 2018, Systematic revision of the Plectopylinae (Gastropoda, Pulmonata, Plectopylidae), European Journal of Taxonomy 455, pp. 1-114 : 75

Genus Plectopylis Benson, 1860

Plectopylis Benson, 1860: 244 .

Type species

Helix achatina Pfeiffer, 1845 by subsequent designation (Pilsbry 1894). Helix achatina Pfeiffer, 1845 is a junior homonym of Helix achatina Gmelin, 1791 . The valid name of the species is Plectopylis bensoni Gude, 1914 .

Species included

Plectopylis anguina ( Gould, 1847) , P. bensoni Gude, 1914 , P. cairnsi Gude, 1898 , P. crassilabris sp. nov., P. cyclaspis Benson, 1859 , P. karenorum W. Blanford, 1865 , P. linterae Möllendorff, 1897 , P. malayana sp. nov. and P. thompsoni sp. nov.

Diagnosis

Shell sinistral, flat, widely umbilicated, usually thick; protoconch smooth (matt) or with small tubercles, usually with irregular, low growth ridges (wrinkles); apertural fold present; parietal wall with two vertical lamellae, which are fused at their upper ends forming a structure resembling the Greek letter lambda (λ); palatal side with a vertical plate formed by the accretion of two plicae (the fourth and the fifth), and three horizontal plicae above and one below that plate.

Inner wall of penis sculptured with multiple, usually serrate parallel folds, and sometimes calcareous crystals; penial caecum usually absent, or a vestigial caecum might be discernible; retractor muscle inserts on penis-epiphallus transition (or on caecum); attached to penis with weak muscle fibres, it is shorter than penis, internally with a few parallel folds; vas deferens slender, usually thickened near its proximal end; vagina mostly short; bursa copulatrix with a slender stalk and a bursa of variable length; diverticulum short and thick, ovoid.

Differential diagnosis

See differential diagnosis and remarks under Chersaecia .

Distribution

Southern Myanmar, northern Malaysia and north-eastern India.

Remarks

Table 3 summarizes the key characters of species of Plectopylis .