Camaena yulinensis Zhou, Wang & Hu, 2020

Wang, Pei, Hu, Mei-Ling, Lin, Jun-Hong, Yang, Hai-Fang, Li, Xiao-Jing & Zhou, Wei-Chuan, 2020, Descriptions of four new dextral land snails of the genus Camaena (Gastropoda, Eupulmonata, Camaenidae) from south China, ZooKeys 996, pp. 37-58 : 37

Camaena yulinensis Zhou, Wang & Hu sp. nov. Figures 3D , 4 , 5D , 9 , Tables 3, 4, 5

Type material.

Holotype. [FJIQBC 19460] Shell height 21.0 mm, shell width 40.5 mm, height of aperture 13.5 mm, width of aperture 18.2 mm, 21 September 2014, collected from the type locality.

Paratype. [FJIQBC 19461-19466] 6 specimens: 3 live adults, 3 empty adult shells, 4 November 2013; [FJIQBC 19468-19472] 5 specimens: 3 live adults, 2 empty juvenile shells, 21 September 2014.

Type locality.

Longquan cave, Yulin, Guangxi, China (22°36'41.24"N, 109°45'21.36"E).

Etymology.

The name of the new species refers to the type locality.

Diagnosis.

Shell. Shell dextral, large, thin, fragile, and slightly lucent, low and flat conical. 4.5 whorls, the front whorls increasing slowly. Spire relatively low. Body whorl rapidly expanded. Shell light yellowish with clear and dense growth lines and spiral bands on the surface. Apex quite blunt. Suture shallow. The protoconch surface smooth for most individuals, but a few are rough. Growth lines clear near the outer side of suture under 32 × stereomicroscope. Last whorl with carinate periphery, a thin reddish brown spiral band on the carina, and many reddish brown spiral bands of different thickness on the upper and lower parts. Aperture lunate. Peristome reflected, flesh-colored, thin, sharp. Columellar lip reflected. Umbilicus reddish brown, open, large, and only 1/3 covered. Inner lip attached to body whorl, forming translucent callus.

Soft body. Pale yellow with irregular black lines. Tentacles dark brown.

Reproductive system. Bursa copulatrix oval, large, with long and tapering pedunculus. Flagellum long and slightly thick, tapering distally. Vas deferens short and thin. Epiphallus medium length and slightly thick. Penis retractor muscle short and wide. Penis short and swollen at distal 1/3, with longitudinal, thin, smooth pilasters internally. Verge conical, large, opened terminally, with some irregular wrinkles on the surface.

Habitat.

The species was found on limestone in Yulin city, Guangxi province.

Distribution.

Only known from the type locality.

Remarks.

Camaena yulinensis sp. nov. differs from C. longsonensis and C. jinpingensis in the key characteristic of large open umbilicus. This new species not only has spiral bands with different thickness on the body whorl but also has a flesh-colored peristome compared to C. vorvonga . The differences between this species and the other three new Camaena species herein have already been described above.

P -distances of the COI gene between C. yulinensis sp. nov. and the other dextral congeners ranges from 0.092 to 0.202 (Table 3 ) and the phylogenetic topology tree supports the establishment of this new species.

Figures

Figure 3. Photographs of the four new species A Camaena funingensis sp. nov. (holotype, FJIQBC 19340, Laolida, Funing, Yunnan, China) B Camaena gaolongensis sp. nov. (holotype, FJIQBC 19353, Dayao, Gaolong, Guangxi, China) C Camaena maguanensis sp. nov. (FJIQBC 19405, Huazhige, Maguan, Yunnan, China) D Camaena yulinensis sp. nov. (FJIQBC 19460, Longquan cave, Yulin, Guangxi, China). Scale bars: 10 mm.

Figure 4. Photographs of three camaenids A Camaena vorvonga (Pingxiang, Guangxi, China) B Camaena jinpingensis (Jinping, Yunnan, China) C Camaena longsonensis (Lang-Son, Vietnam). Scale bars: 10 mm.

Figure 5. Ecological photographs of snails A Camaena funingensis sp. nov. (Laolida, Funing, Yunnan, China) B Camaena gaolongensis sp. nov. (Dayao, Gaolong, Guangxi, China) C Camaena maguanensis sp. nov. (Huazhige, Maguan, Yunnan, China) D Camaena yulinensis sp. nov. (Longquan cave, Yulin, Guangxi, China).

Figure 9. Reproductive system of the snail Camaena yulinensis sp. nov. (FJIQBC 19460, Longquan cave, Yulin, Guangxi, China) A reproductive organ B penis C verge D inner penial wall. The arrow indicates opening position of the verge.