Diaphera, ALBERS, 1850

Sutcharit, Chirasak, Naggs, Fred, Wade, Christopher M., Fontanilla, Ian & Panha, Somsak, 2010, The new family Diapheridae, a new species of Diaphera Albers from Thailand, and the position of the Diapheridae within a molecular phylogeny of the Streptaxoidea (Pulmonata: Stylommatophora), Zoological Journal of the Linnean Society 160 (1), pp. 1-16 : 5

GENUS DIAPHERA ALBERS, 1850

Type species: Cylindrella cumingiana Pfeiffer, 1845 , by original designation; lectotype BMNH 20080230 ( Fig. 1A ); type locality: the Philippines (‘in grass, Guimaras, the Philippines’ , given on original label).

Diagnosis: Shell ovate to cylindrical, thin, transparent, and glossy, surface smooth or sculptured; apex obtuse, surface smooth, subsequent whorls smooth or with radial ribs; part of last whorl always detached; aperture circular to ovate; lip expanded and slightly reflexed; apertural dentition usually comprised of parietal, palatal, basal, and columellar lamellae. Radula plate narrow; teeth lanceolate, central tooth minute, lateral and marginal teeth similar with long cusp. Genitalia with well-developed penis; penial sheath, verge, and spines are absent.

Remarks: Diaphera currently includes 39 nominal species that range from Burma, Thailand, Cambodia, and the Philippines to Kalimantan ( Blanford, 1899; Bruggen, 1975; Richardson, 1988; Vermeulen, 1990; Schileyko, 2000). In Thailand Diaphera can be distinguished conchologically from similar genera such as Sinoennea (with six to seven whorls) by possessing a greater number (eight to 20) of more elongate, cylindrical whorls; partially detached last whorl and ovate aperture ( Tryon, 1885; Zilch, 1960; Richardson, 1988; Schileyko, 2000).

Diaphera was treated as a subgenus of Gibbus Montfort, 1810 by Tryon (1885) and of Gulella Pfeiffer, 1856 by Thiele (1931). Zilch (1960) subsequently treated Diaphera as a distinct genus. Richardson (1988) placed 46 species from the Philippines and Indochina in Diaphera . However, Richardson’s inclusion of the two pupiform Madagascan species, Gulella miaryi ( Fischer-Piette & Bedoucha, 1964) and Gulella gallora ( Fischer-Piette, Blanc & Salvat, 1975) , both of which lack a detached last whorl, seems unjustified (see Fischer-Piette & Bedoucha, 1964; Fischer-Piette et al., 1975). The Madagascan taxa are likely to be part of or allied to the Gulella group. Eight cylindrically shelled species from the Philippines Ennea sericina Möllendorff (1887) , Ennea hidalgoi Möllendorff, 1888 , Ennea cardiostoma Quadras & Möllendorff, 1894 , Ennea nitidula Quadras & Möllendorff, 1894 , Ennea otostoma Quadras & Möllendorff, 1894 , Ennea cylindrica Quadras & Möllendorff, 1895 , Ennea cristatella Möllendorff, 1896 , and Ennea samarica Möllendorff, 1896 were placed in Diaphera by Zilch (1961) and Richardson (1988). However, these taxa lack a partially detached last whorl and are thus more likely to be related to Ennea H. & A. Adams, 1855. Richardson (1988) followed Kobelt (1904) and Blanford & Godwin- Austen (1908) in placing Ennea brevicollis Blanford, 1899 in Sinoennea , but this species possesses a multiwhorled turriform shell with detached body whorl and belongs in Diaphera (Table 2).

Figures

Figure 1. A, shell morphology of Diaphera cumingiana (Pfeiffer, 1845) (lectotype BMNH 20080230). B–G, morphology of shell and radular and living animals of Diaphera prima sp. nov. B, the shell and C, the aperture of holotype (CUMZ 3544) showing lamellae. D, juvenile specimen showing apertural lamellae (paratype CUMZ 3630). E, F, living animals (paratype CUMZ 3629): E, shell height 6.5 mm; and F, shell height 6.8 mm. G, radula morphology (paratype CUMZ 3545); arrow on top-right inset indicates the central tooth. H, I, morphology of shell of Diaphera saurini Benthem Jutting, 1962. H, the shell and I, aperture of holotype (ZMA 3.62.016) showing lamellae. Abbreviations: P, parietal lamella; Pl, palatal lamella; Bl, basal lamella; Cl, columellar lamella.