Bellardiella (Bellardiella) kovacsi, Varga & Páll-Gergely, 2017

Varga, András & Páll-Gergely, Barna, 2017, A review of Bellardiella Tapparone-Canefri, 1883, with descriptions of a new subgenus and two new species (Gastropoda: Cyclophoroidea: Pupinidae), Raffles Bulletin of Zoology 65, pp. 386-394 : 389

Bellardiella (Bellardiella) kovacsi new species

( Fig. 2 F–L)

Type material. Holotype ( MMGY 74592 , probably flotsam shell; H = 17.85 mm, D = 9.5 mm, Fig. 2 G–L), Indonesia, West Papua, Batanta Island, dry valley of the Kaliselatan River , 0°54.513′S, 130°35.883′E, coll. T. Kovács, R. Horváth, P. Juhász, K. Sauyai & R. Sauyai, 14 February 2016 ; Paratype ( MMGY 74593 ; flotsam, weathered shell), Indonesia, West Papua, Batanta Island , valley of “Wilson” stream, 0°49.385′S, 130°48.364′E, coll. T. Kovács, R. Horváth & P. Juhász, 19 February 2017 ; Paratype ( MMGY 74594 , Fig. 2F ), Indonesia, West Papua, Batanta Island, valley of Warmon stream, between the lower and upper waterfall (0°50.076′S, 130°42.900′E, and 0°50.388′S, 130°42.586′E), coll. T. Kovács, R. Horváth & P. Juhász, 20 February 2017, collected among leaf litter at the base of a large tree ).

Diagnosis. A large (H: 17.1–17.9 mm, D: 8.9–9.5 mm) Bellardiella species with relatively slender ovoid, nearly smooth shell, open, deep umbilicus, rounded aperture, well-developed sinulus, a strong parietal callus, a strongly thickened peristome, and an umbilical tube, which is attached to the peristome.

Description. Shell ecru-cream coloured (maybe due to weathering) or brownish, matt, elongate ovoid with pointed apex; the increase of the whorls is rather regular, slow at the beginning, and increasing in the last approx. 2.5 whorls; there are 6.3 whorls out of which the protoconch consists of approx. 2.3 whorls, although the boundary between the protoconch and the teleoconch is hardly discernible; protoconch smooth; teleoconch with very fine growth lines; growth lines overall slightly oblique to shell axis, but near the suture they are slightly bent, becoming nearly perpendicular to the suture; sculpture of body whorl slightly stronger than that of preceding whorls; the very slightly bulging whorls are separated by a shallow suture; the last approx. quarter whorl has a slight subsutural furrow ( Fig. 2I ); aperture rounded with a small, narrow sinulus, resulting in a pear-shaped outline; sinulus continues as a short, shallow groove inside the aperture; aperture nearly parallel with shell axis, only slightly oblique from lateral view (basal part situated slightly more anteriorly than parietal part); peristome continuous with strong parietal callus and inner and outer peristome; outer peristome strongly thickened, slightly expanded and reflected only on the basal area; lower part of peristome approx. twice as thick as the upper part (observed from lateral view, Fig. 2H ); outer peristome follows arc of sinulus, rounded at parietal and basal part, and slightly angled at parietal-columellar transition; inner peristome slightly protruding in anterior direction, blunt; its margin with very slight notch just before tube, indicating that the tube might have been in contact with inner margin in an earlier stage of the development; umbilicus rather wide, deep, shows the last whorl only; umbilical tube slightly S-shaped, follows columellar part of peristome, and points backwards (away from the peristome); its inner end not visible, its outer ending slightly compressed, circular. Operculum and anatomy unknown.

Measurements. H = 17.1–17.9 mm, D = 8.9–9.5 mm, AH = 7.6–7.8 mm, AW = 6.4–6.6 mm (n = 3).

Differential diagnosis. Bellardiella kovacsi new species has the most slender shell among all of its congeners, therefore can be distinguished from them at first sight. Bellardiella martensiana has a more ovoid shell with slightly more bulging whorls, much stronger parietal callus and the peristomal lip is rounded from lateral view (angled in B. kovacsi new species). Based on the formation of the aperture Bellardiella kovacsi new species is most similar to B. fabula because of the thick peristome, the strong callus and the narrow sinulus, but differs from the new species in the much larger, slender shell, and the comparatively smaller, rounded peristome (rather rectangular in B. fabula ). Bellardiella crassilabris is also similar to the new species in terms of the formation of the aperture, but that species is smaller and more corpulent than the new species, and its thick, reflected peristome almost closes the umbilicus. Bellardiella minor has a closed umbilicus, therefore differs from all other Bellardiella species.

Type locality. Indonesia, West Papua, Batanta Island, dry valley of the Kaliselatan River , 0°54.513′S, 130°35.883′E .

Distribution. The new species is known from three localities in Batanta Island (Raja Ampat Islands in West Papua province, Indonesia).

Etymology. This new species is dedicated to and named after Tibor Kovács, a prominent entomologist and friend of the authors, who collected the specimens.

Figures

Fig. 2. Shells of Bellardiella species. A–E, neotype of B. crassilabris Möllendorff, 1899 (NHMUK 1910.12.30.97); F–L, Bellardiella (Bellardiella) kovacsi new species. F, paratype (MMGY 74594); G–L, holotype (MMGY 74592). Scale represents 5 mm. Photos: B. Páll-Gergely (A–E) and A. Varga (F–L).