Phuphania costata, Tumpeesuwan & Tumpeesuwan, 2014

Tumpeesuwan, Chanidaporn & Tumpeesuwan, Sakboworn, 2014, Phuphania costata, a new species of dyakiid land snail (Pulmonata: Dyakiidae) from Phu Pha Lom limestone area, Loei Province, northeastern Thailand, Raffles Bulletin of Zoology 62, pp. 352-357 : 353-354

Phuphania costata , new species

Figs. 2–5 ; Table 1

Phuphania sp. : Tanmuangpak et al., 2012: 18, 20, 22–24

Type material. Holotype: NHMSU-0002 ( Fig. 2 ). Measurements: shell height 20.7 mm, shell width 29.9 mm; type locality: Phu Pha Lom Limestone Mountain , Loei Province, northeastern Thailand. coll. K. Tanmuangpak, October 2012 . Paratype: NHMSU-0003 (63 shells); ZRC MOL (1 shell); NMLRU-0001 (1 shell); ZRCBUU 03395 (1 shell), coll. K. Tanmuangpak, October 2011 – October 2012 .

Etymology. “ costata ” from the dense and regularly radial ribs on the dorsal part of the shell surface.

Diagnosis. The new species possesses 2–4 clusters of internal ducts within the amatorial organ gland, fused lobes forming very thick sac over the amatorial organ, and the vas deferens enters the epiphallus apically ( Fig. 4 ; Table 1 ). Dorsal shell surface possesses dense and regularly radial ribs.

Description. Shell: Dextral, sub-depressed, height 14.9–20.7 mm, shell width 22.7–29.9 mm, 5¾ convex whorls, slightly thin, body whorl large, slightly angulated at periphery, fulvous above, embryonic whorls with fine radial ribs, subsequent whorls with distinct radial ribs, 28–31 ribs per 10 mm ( Fig. 2A, B ). Aperture slightly large, aperture height 10.2–13.1 mm, aperture width 12.4–16.1 mm, crescent shape, distinctly oblique, lip neither expanded nor reflected. Umbilicus narrow.

Body: Ground colour of body grey, marked with black spots. Foot sole undivided, caudal horn without overhanging lobe, caudal foss with short vertical slit in tail ( Fig. 3 ).

Genital system: Atrium (at) very short, nearly absent. Penis (p) short cylindrical. Epiphallus (ep) proximal part clavate, proximal end more swollen than distal end and penis, distal end equal in size to distal part. Penial retractor muscle (pr) slightly swollen at the middle, inserts near distal end of epiphallus.Vas deferens (vd) narrow, longer than penis and vagina (v), entering epiphallus apically.Amatorial organ (am) large, stoutly cylindrical sac. Amatorial organ gland (amg) forms thick crescent shaped cap connect to the amatorial organ and consists of 2–4 clusters of internal duct of amatorial organ gland (camg). Free oviduct (fo) rather short. Large and elongate gametolytic sac (gs) connects to the base of the amatorial organ, which possesses an apical ligament that attaches to the prostate gland (pg) ( Figs. 4 A–D).

Radula: Each row of teeth is arranged in a wide angled V formation, where the central tooth is lanceolate and tricuspid. Lateral teeth blade-shaped, tricuspid with tiny lateral cusps, endocone closer to the tip of the central cusp than ectocone ( Fig. 5 A–C). Size and shape of teeth gradually changes to slim finger shape and endocone absent to form bicuspid at the last 7 th– 8 th teeth from the outermost lateral teeth ( Fig. 5D, E ). Marginal teeth 12–20, unicuspid, narrow, elongated and finger-shaped ( Fig. 5F, G ).

Figures

Fig. 2. Phuphania costata, new species, Phu Pha Lom Limestone Mountain, Loei Province. Holotype (NHMSU-0002): A, dorsal view; B, apertural view; C, ventral view.

Fig. 3. Phuphania costata new species. Phu Pha Lom Limestone Mountain, Loei Province. Paratype (NHMSU-0003).

Fig. 4. Phuphania costata, new species. Genital system of paratype (NHMSU-0003): A, internal structure of amatorial organ gland (amg); B, genital system; C, schematic drawing of internal structure of amatorial organ gland (amg); D, genital system. (scale bar provided applies A through D).

Fig. 5. Phuphania costata, new species. Radula of paratype (NHMSU-0003): A, left lateral teeth; B, central teeth (indicated by letter ‘C’) and lateral teeth; C, right lateral teeth; D–E, transitional from tricuspid to bicuspid lateral teeth and unicuspid marginal teeth on both left and right side of central teeth; F, left marginal teeth; G, right marginal teeth.