Semisulcospira guilinensis Chen & He, 2024

He, Yue Ming, Lu, Yi Zhi, Fu, Zhi Yuan, Xiang, Hong Quan & Chen, Hui, 2024, Description of 17 new species of Semisulcospiridae (Gastropoda: Cerithioidea) from southern China based on morphological and molecular evidence, Ecologica Montenegrina 75, pp. 12-32 : 25-26

Semisulcospira guilinensis Chen & He , sp. nov.

https://zoobank.org/ urn:lsid:zoobank.org:act:22979BCF-34AA-4888-ADF6-3827CC721A3E

( Figs. 1 O , 2 O )

Material examined. 4 ex. From Lijiang River , Sanjie Town , Lingchuan County, Guilin City, Guangxi Province, China; 25.47°N, 110.40°E, May 2023 by Hao- Fei Fan leg.

Holotype. NNUH20240101 , shell height 20.31 mm, width 9.02 mm, height of the body whorl 9.88 mm.

Paratypes. 3 ex. NNUH20240102–4 , shell height 19.12–19.46 mm, width 8.04–8.37 mm, height of the body whorl 9.02–9.61 mm, locality and habitat same as holotype .

Locus typicus. Lijiang River, Sanjie Town, Lingchuan County, Guilin City, Guangxi Province, China; 25.47°N, 110.40°E.

Etymology. The specific name " guilinensis " is derived from Guilin city, the collection location of the specimen. We suggest the Chinese common name as " 桂R短沟ĸ ".

Description. Shell small, thick, solid, conical, brown, with black band; shell comprising eight to nine whorls, body whorl swollen, taking up most of the shell about 48%, surface smooth, growth lines not obvious, without spiral ribs. Apex eroded. Suture low. Aperture ovate, lip thin, inner lip slightly thickened and smooth, white, outer lip light brown. Umbilicus absent.

Operculum. ( Fig. 2 O ) Ovate, smaller than aperture, corneous, thin, brown, length 4.26 mm, width 3.12 mm, and the nucleus located at the bottom left about 1/4.

Radula. ( Fig. 3 O ) Central teeth with triangle-shaped pointed major cusp, and 3–4 smaller cusps on each side. Lateral teeth with pointed major cusp, and 2–3 smaller cusps on each side. Inner marginal teeth with four and outer with six to seven flattened, rounded denticles.

Anatomy. Snout, foot and tentacles grey. Snout broad, with a brown pigmented. squarish, with long cephalic tentacles, tentacles roughly greater than snout in length. Without ovipositor pore on side of neck below right cephalic tentacle.

Remarks. Outer marginal teeth have six to seven smaller cusps of S. guilinensis sp. nov., which is a significant feature that distinguishes other Semisulcospira species. Semisulcospira guilinensis sp. nov. is most similar to S. pleuroceroides (Bavay & Dautzenberg, 1910) , but can nevertheless be easily separated by the operculum nucleus located at about 1/4 (vs. located at the bottom left edge 1/ 3 in S. pleuroceroides ), and the operculum of S. guilinensis sp. nov. is elliptical, while that of S. pleuroceroides is approximately circular. The new species can also be clearly distinguished from other Semisulcospira congeners by the following features: shell smooth (vs. shell sculptured in S. ningpoensis (Lea, 1857) , S. cinnamomea (Gredler, 1887) and S. gredleri (Boettger, 1886)) , inner marginal teeth with four flattened denticles (vs. six flattened in S. calculus (Reeve, 1860)) .

Habitat and distribution. This species was collected in the Lijiang River in Sanjie Town, Lingchuan County, Guilin City, Guangxi Province. The species inhabits rivers with a depth of less than 50 cm, slow water flow, and a substrate made of stones and sand.

Figures

Figure 1. Hua suifuensis (A) Holotype, NNUH20241501; H. yiliangensis sp. nov. (B) Holotype, NNUH20241301; H. rayeae sp. nov. (C) Holotype, NNUH20241701; H. yunong sp. nov. (D) Holotype, NNUH20241801; H. heimao sp. nov. (E) Holotype, NNUH20241601; H. jiuxiangensis sp. nov. (F) Holotype, NNUH20241901; H. penicillata sp. nov. (G) Holotype, NNUH20240201; H. wudangensis sp. nov. (H) Holotype, NNUH20240301; H. pyriformis sp. nov. (I) Holotype, NNUH20240401; H. censongyangi sp. nov. (J) Holotype, NNUH20240501; H. jundazhaoi sp. nov. (K) Holotype, NNUH20240601; H. jiahaojingi sp. nov. (L) Holotype, NNUH20240701; H. mileensis sp. nov. (M) Holotype, NNUH20240901; Semisulcospira fasciata sp. nov. (N) Holotype, NNUH20240901; S. guilinensis sp. nov. (O) Holotype, NNUH20240101; S. tigra sp. nov. (P) Holotype, NNUH20241001; S. sangpuensis sp. nov. (Q) Holotype, NNUH20240801; K. zhiyuanfui sp. nov. (R) Holotype, NNUH20240801. Scale bar = 10 mm.

Figure 2. Opercula of Semisulcospiridae species from China. Hua suifuensis (A); H. yiliangensis sp. nov. (B); H. rayeae sp. nov. (C); H. yunong sp. nov. (D); H. heimao sp. nov. (E); H. jiuxiangensis sp. nov. (F); H. penicillata sp. nov. (G); H. wudangensis sp. nov. (H); H. pyriformis sp. nov. (I); H. censongyangi sp. nov. (J); H. jundazhaoi sp. nov. (K); H. jiahaojingi sp. nov. (L); H. mileensis sp. nov. (M); Semisulcospira fasciata sp. nov. (N); S. guilinensis sp. nov. (O); S. tigra sp. nov. (P); S. sangpuensis sp. nov. (Q); K. zhiyuanfui sp. nov. (R). Scale bar = 3 mm.

Figure 3. Radulae of Semisulcospiridae species from China. Hua suifuensis (A); H. yiliangensis sp. nov. (B); H. rayeae sp. nov. (C); H. yunong sp. nov. (D); H. heimao sp. nov. (E); H. jiuxiangensis sp. nov. (F); H. penicillata sp. nov. (G); H. wudangensis sp. nov. (H); H. pyriformis sp. nov. (I); H. censongyangi sp. nov. (J); H. jundazhaoi sp. nov. (K); H. jiahaojingi sp. nov. (L); H. mileensis sp. nov. (M); Semisulcospira fasciata sp. nov. (N); S. guilinensis sp. nov. (O); S. tigra sp. nov. (P); S. sangpuensis sp. nov. (Q); K. zhiyuanfui sp. nov. (R).