Sulcospira kawaluensis, Marwoto & Isnaningsih, 2012

Marwoto, Ristiyanti M. & Isnaningsih, Nur R., 2012, The Freshwater Snail Genus Sulcospira Troschel, 1857 From Java, With Description Of A New Species From Tasikmalaya, West Java, Indonesia (Mollusca: Gastropoda: Pachychilidae), Raffles Bulletin of Zoology 60 (1), pp. 1-10 : 4-6

Sulcospira kawaluensis , new species

( Fig. 2A–G )

Material examined. — Holotype: 1 ex. ( MZB Gst.15.059), on sandy and rocky substrate, water depth <0.4 m, in River Cibangbay (07°25'14.7"S, 108°11'34.9"E), Kawalu subdistrict, Tasikmalaya, West Java, Indonesia, coll. Heryanto & Nova, 21 Oct.2009.

Paratypes: 35 ex. ( MZB Gst.15.060), same habitat and locality as holotype; 16 ex ( MZB Gst.15.061), Mangunrejo subdistrict (07°22'05.2"S, 108°05'22.8"E) Tasikmalaya, West Java, Indonesia, coll. Heryanto & Nova, 23 Oct.2009 ; 18 ex. ( MZB Gst.8545), small Cisereuh River , Kawalu subdistrict, Tasikmalaya, W. Java, Indonesia, coll. M. Djajasasmita, 26 Oct.1980 .

Description. — Shell medium sized, thick, ovately conic, olive brown or dark brown to black. Usually with dark brown flames at the body whorl. Earlier whorls in adult specimens almost always corroded, with only four to six flattened whorls remaining. Suture not deep. Shell smooth, without spiral lirae, except for three to seven at the base of body whorls. Spire angle about 60°. Aperture widely ovate, somewhat expanded at the base; inner part white to brownish. Peristome sharp; columella thickened. Operculum oval with three whorls increasing in diameter, and a sub-central nucleus ( Fig. 2D ). Shell dimensions are given in Table 2.

External and internal morphology ( Figs. 3A , 5A ). Head foot dark grey to black, mantle edge straight, dark grey or pale pigmented. Body coiled in 2.5 whorls, mantle cavity about 1.5 whorls. Head, tentacle, and neck pigmented dark grey to black. Hypobranchial gland visible, ctenidium long (> 7 mm length), osphradium simple, pale, about half of the ctenidium length. Stomach has a simple sorting area formed by two transverse folds and crescent-shaped thickening. Inner crescent fold undulated, gastric pad thick and large supporting a thin cuticular gastric shield ( Fig. 3B ).

Radula ( Fig. 4A, B ). — Taeniglossate with 190 rows, 21.20– 23.14 mm long (n = 3). Central tooth with very large, almost triangle- shaped pointed major denticle, accompanied by two very much smaller denticles at each side. Glabella broad and the basal margin slightly rounded. Lateral teeth with enlarged, pointed major denticles and two much smaller denticles on each side as well. Marginal teeth slightly concave, tips curved and comparatively long, with two denticles each, the outermost ones are much enlarged.

Reproductive system ( Fig. 5A, B ). — Female with subhaemocoelic brood pouch located well behind buccal mass, occupying very large part of visceral cavity. Females containing 77–108 embryonic shelled (n of adult female = 6) all in similar size, about 1.45 mm height. Pallial oviduct about 7 mm long. A free medial lamina supports two sperm gutters, a spermatophore bursa, and a seminal receptacle.

Embryonic shell ( Fig. 6A, B ). — Conical, dome-shaped, with two whorls; protoconch smooth with fine granular texture. Second whorl with faint spiral lirae. Height of shell 1.45 mm, diameter of protoconch 0.5 mm.

Distribution. — Only known from Kawalu subdistrict at Tasikmalaya, West Java.

Etymology. — The specific name kawaluensis is an adjective referring to the name of the sub district Kawalu at Tasikmalaya, where the River Cibangbay is situated; of female gender.

Figures

Fig. 2. Shell and operculum of S. kawaluensis new species: A–C, holotype (MZB Gst.15.059); D, operculum of a paratype; E–G, paratypes (MZB Gst.8.545). Scale bar = 10 mm.

Fig. 3. External and internal morphology of S. kawaluensis new species: A, coiling animal; B, detail stomach. Abbreviations: cr, crescent folds; ct, crescent thickenings;dg, digestive gland; dgd, digestive gland duct; gp, gastric pad; lf, lateral fold; me, mantle edge; msc, columella muscle; sa, sorting area; sl, sole; ss, opening to style sac; stm, stomach. Scale bar = 1 mm.

Fig. 5. External anatomy of a female S. kawaluensis new species: A, anatomy of a female exposed subhaemocoelic brood pouch filled with embryonic shells; B, schematic representation of the pallial oviduct morphology. Small letters (a–d) indicate approximate location of anterior part of cross section. Abbreviations: cte, ctenidium; og, oviductal groove; op, operculum; osp, osphradium; po, pallial oviduct; sb, spermatophore bursa; sg, sperm gutter; 2sg, second sperm gutter; sh, subhaemocoelic brood pouch; sr, seminal receptacle. Scale bar =1 mm.

Fig. 4. Radular morphology: A–B, SEM images of a radular fragment of S. kawaluensis new species, showing central, lateral, marginal teeth: A, view from above; B, anterior viewed at 45° showing the shape of radular denticles. C–D, SEM images of radular fragment of S. testudinaria showing central, lateral, marginal teeth: C, view from above; D, anterior viewed at 45° showing the shape of radular denticles. Scale bar = 100 μm.

Fig. 6. Embryonic shells from brood pouches:A, B, S. kawaluensis new species; C, D, S. testudinaria. Scale bar = 0.5 mm.