Parasinoennea, Páll-Gergely & Hunyadi & Grego & Sajan & Tripathy & Chen, 2020

Páll-Gergely, Barna, Hunyadi, András, Grego, Jozef, Sajan, Sheikh, Tripathy, Basudev & Chen, Zhe-Yu, 2020, A review of the Diapheridae (Gastropoda: Eupulmonata: Streptaxoidea), with special emphasis on India and Myanmar, Raffles Bulletin of Zoology 68, pp. 682-718 : 696

Parasinoennea Z.-Y. Chen & Páll-Gergely, new genus

Type species. Ennea splendens Möllendorff, 1882 ( Fig. 9A–E ).

Diagnosis. Shell ovate, glossy; aperture triangular, adnate to the penultimate whorl.

Differential diagnosis. The shell shape of Parasinoennea , new genus, is oval, whereas it is usually elongated and cylindrical in Sinoennea . The teleoconch of Parasinoennea is usually smooth, sometimes ornamented by low, blunt ribs, but is always glossy. In contrast, the ribs of Sinoennea are usually sharp and elevated, and the shell has a less glossy appearance. The main difference is in the aperture shape, which is triangular (in some species the palato-basal part distorted laterally) in Parasinoennea , new genus, but elongated oval and cylindrical in Sinoennea . The aperture is adnate (i.e., the parietal callus is attached to the penultimate whorl) in Parasinoennea , new genus, and the parietal callus is always clearly separated from the penultimate whorl in Sinoennea . The apertural dentition is not clearly different, although Parasinoennea , new genus, often possesses two tubercles (denticles) on the columellar peristome (anterior to the columellar lamella), which has not been observed in any Sinoennea species to our knowledge. The upper denticle is probably homologous with the upper denticle of Pupennea , new genus, and Platylennea , new genus.

Included species. Parasinoennea demangei ( Bavay & Dautzenberg, 1912) (northern Vietnam), P. formica ( Bavay & Dautzenberg, 1912) (northern Vietnam), P. splendens splendens ( Möllendorff, 1882) (Guangdong, China), P. splendens hongkongensis Möllendorff, 1885 ( Hongkong, China), P. ovulum ( Bavay & Dautzenberg, 1912) (northern Vietnam) ( Figs. 9F–N , 22H ).

Etymology. The Greek prefix para- (παρά, meaning beside, next to, against, etc.) is attached to Sinoennea to show that it is separated from that genus. Grammatical gender: feminine.

Distribution. South China (Guangxi, Guangdong, Hong Kong, Jiangxi) and northern Vietnam ( Fig. 10 ).

Remarks. Sinoennea longtanensis S. Ouyang, X. -M. Liu & X.-P. Wu, 2012 does not differ from typical P. splendens (examined material: SMF 42775, lectotype, see Fig. 9A–E ) in any traits. Therefore, we considered it a synonym of the latter.

Figures

Fig.9. Shells of Parasinoennea, new genus.A–E, Parasinoennea splendens (Möllendorff, 1882) SMF 42775 (lectotype); F–N, Parasinoennea ovulum (Bavay & Dautzenberg, 1912), MNHN-IM-2000-30970 (syntype). Both scales represent 1 mm; scale “a” refers to figs. A–E and H, scale “b” refers to figs. F–G and I–N.

Fig. 22. Apertures of Streptaxidae (A) and Diapheridae (B–P). A, Gulella (Huttonella) bicolor (Hutton, 1834); B, Rowsonia beddomei (W.T. Blanford, 1881); C, Platylennea subcostulata (W.T. Blanford, 1881); D, Pupennea planguncula (Benson, 1863); E, Diaphera polita, Páll-Gergely new species; F, Diaphera cylindrelloidea (Stoliczka, 1871); G, Bruggennea cf. bongi (Dance, 1970), H, Parasinoennea ovulum (Bavay & Dautzenberg, 1912); I, Sinoennea otostoma Páll-Gergely, A. Reischütz & Maassen in Páll-Gergely, Reischütz, Maassen, Grego & Hunyadi, 2020; J, Sinoennea infantilis Páll-Gergely & Grego in Páll-Gergely et al., 2020; K, Sinoennea variabilis Páll-Gergely & Grego in Páll-Gergely et al., 2020; L, Sinoennea sutchariti Páll-Gergely & Hunyadi in Páll-Gergely et al., 2020; M, Sinoennea montawana Páll-Gergely & Hunyadi, new species; N, Sinoennea angustistoma Páll-Gergely, A. Reischütz & Maassen in Páll-Gergely et al., 2020, O, Sinoennea woodthorpei (Peile, 1929); P, Sinoennea fartoidea (Theobald, 1870). Not to scale.

Fig. 10. Distribution of Parasinoennea, new genus, Sinoennea Kobelt, 1904, Pupennea, new genus, Platylennea, new genus, and Rowsonia, new genus.