Laeocathaica qishilii Wu, 2023

Wu, Min, Shen, Wang & Chen, Zhong-Guang, 2023, Land snail diversity in central China: revision of Laeocathaica Moellendorff, 1899 (Gastropoda, Camaenidae), with descriptions of seven new species, ZooKeys 1154, pp. 49-147 : 49

Laeocathaica qishilii Wu sp. nov.

Figs 2A, B , 4 , 35A, B , 36 , 44C , 48A, B , 49A, B

Type material.

Holotype HBUMM08298-spec.1, fma, border of Jiuzhaigou County and Wen County, near point (33.14376°N, 104.246674°E); 2019-IV, coll. Li, Q.-S. Paratypes HBUMM08298-spec.2-8, 7 fma, 3 fma dissected; same data as holotype. HBUMM06779 and HBUMM06778, 2 fma and 1 fms, 1 fma dissected; Shijiba, Wen County, 1193 m a.s.l., 33.102222°N, 104.335556°E, 2011-VIII-10, coll. Wu, M., Xu, Q. and Budha, P.

Measurement of holotype.

Shell height 8.1 mm, maximum diameter 23.7 mm, aperture height 5.6 mm, aperture breadth 10.6 mm, umbilicus diameter 5.6 mm, protoconch whorls 11/2, whorls 55/8.

Diagnosis.

Protoconch with decussate radial and spiral threads. Umbilicus broad and deep, through which protoconch is visible. A bright band present between carina and suture. Beneath carina a dark chestnut band present. Mucous glands two. Penis with two proximal thick internal pilasters fusing into a Y-shaped fork at proximal 1/3. Vagina between atrium and dart sac not elongated. Two proximal accessory sacs on both sides of dart sac, with two pores leading to opening of dart chamber.

Description of shell.

Sinistral, depressed, thin but somewhat solid. Shell with 51/2-57/8 fairly flat whorls. Suture impressed. Protoconch 11/2-15/8 whorls, with decussate radial and spiral threads, on the first whorl of which may be invisible because of weathering or erosion. Growth lines fine, more or less clear. Aperture oblique, peach-shaped, descending. Peristome expanded and reflexed at lower part. Columella oblique. Umbilicus broad, ~ 1/3 of maximum diameter. Protoconch visible through umbilicus. Shell apically in chestnut except white carina, after the first three or four whorls a bright band present between carina and adjacent suture. In umbilical view shell distinctly paler in greyish yellow and just beneath carina a chestnut band present.

General anatomy.

Eversible head wart present. At mantle edge leaf-shaped appendage absent. On internal body wall of head region between ommatophorous insertions with neither glands nor tiny pits. Body greyish brown, central dorsum with pale longitudinal stripes. Sole dirty white. Jaw arcuate, with 3-5 more or less projecting ribs.

Anatomy of genital organs.

Penial sheath short but well developed. Penis of equal thickness, externally simple. Inside penis, two very thick longitudinal pilasters fusing into a Y-shaped fork at proximal 1/3, accompanied with another two thick pilasters, these plasters then change into numerous fine pilasters that distally merge into three short but thick folds near opening of epiphallus. Epiphallic papilla absent. Vas deferens narrow throughout. Vagina between atrium and dart sac not elongated. Accessory sac spherical, solid, inserting into dart sac medially, opening to distal dart chamber. Mucous glands two, each complicatedly branched. Proximal accessory sacs two, symmetrical, dorsally separated and ventrally touching, each with a pore leading to proximal dart chamber. Love dart ~ 6 mm long, apically 2-bladed, medially round-hexagonal. Bursa copulatrix duct equally narrow. Bursa copulatrix pear-shaped.

Etymology.

This new species is named after Mr Li, Qi-Shi, who made this work possible with his field work.

Ecology.

This species is found under rotten wood.

Distribution.

Only known from the type locality.

Remarks.

This new species has a unique protoconch on which decussate radial and spiral threads are present compared to the granulation on this part in the other Laeocathaica species. The new species is conchologically close to Laeocathaica prionotropis , but the former species is apically more depressed, more broadly umbilicate, has a more expanded peristome, a more elongated aperture due to the more prominent carina, is apically evenly brown, and has a smooth shell surface instead of the finely scaly surface in the latter species. The new species shares the inner structure of the dart sac with L. prionotropis . However, they differ in the internal structure of penis: in L. prionotropis , partial pilasters merge into a tubercle, which is missing in the new species. They also differ in the number of tubes of the mucous glands.

Figures

Figure 2. A distribution map of all known species of Laeocathaica Moellendorff, 1899 except L. anceyi (Moellendorff in Ancey, 1889), L. hisanoi Pall-Gergely, 2022, and L. leucorhaphe Moellendorff, 1899 whose precise localities are not known; white dots: the localities where no Laeocathaica species was ever found B distribution of the new species described in this paper, yellow dots: L. qingchuanensis Wu, sp. nov., green dot: L. zhengpingliui Wu, sp. nov., brown dots: L. parapolytyla Wu, sp. nov., white dot: L. qiminglii Wu, sp. nov., pink dot: L. cheni Wu, sp. nov., blue dots: L. qishilii Wu, sp. nov., orange dots: L. nordsiecki Wu, sp. nov. C distribution of L. carinifera (H. Adams, 1870) (green dots), L. qingchuanensis Wu, sp. nov. (yellow dots), and L. stenochone Moellendorff, 1899 (blue dots) D distribution of L. amdoana Moellendorff, 1899 (green dots), L. distinguenda Moellendorff, 1899 (pink dots), and L. tropidorhaphe Moellendorff, 1899 (blue dots) C equivalent to the larger box in (A), B, D equivalent to the smaller box in (A).

Figure 4. Terminal genitalia in the evaginated pouch in Laeocathaica qishilii Wu, sp. nov. (HBUMM 08298 - spec. 8, paratype), showing relative position of dart sac apparatus, vagina, and penis A evaginated pouch of terminal genitalia B the exposed pouch. Arrow indicates the position of the proximal accessory sac. Abbreviations: DS - dart sac; Dt - love dart; EDC - entrance of dart chamber; EOV - external opening of vagina; EOP - external opening of penis; MG - mucous glands; P - penis; PAS - proximal accessory sac; PO - opening of proximal accessory sac leading to dart sac chamber or dart chamber; Va - vagina.

Figure 35. A, B Laeocathaica qishilii Wu, sp. nov. A holotype, HBUMM 08298 - spec. 1 B paratype, HBUMM 08298 - spec. 2 C, D L. qiminglii Wu, sp. nov. C holotype, HBUMM 08422 - spec. 1 D paratype, HBUMM 08448 - spec. 1.

Figure 36. Genital anatomy of Laeocathaica qishilii Wu, sp. nov., HBUMM 08298 - spec. 1, holotype A general view B ventral view of dart sac apparatus C left view of dart sac apparatus D cross-section of dart sac at the position arrowed in (A). Abbreviations: AS - accessory sac; At - atrium; BC - bursa copulatrix; BCD - bursa copulatrix duct; DS - dart sac; DtC - a chamber containing love dart; Ep - epiphallus; FO - free oviduct; MG - mucous glands; P - penis; PAS - proximal accessory sac; PO - opening of proximal accessory sac leading to dart chamber; PR - penial retractor muscle; PS - penial sheath; Va - vagina; VD - vas deferens.

Figure 44. Internal view of penis A, B Laeocathaica tropidorhaphe Moellendorff, 1899 A general view, HBUMM 05619 - spec. 1 B proximal penis, HBUMM 05664 - spec. 1 C L. qishilii Wu, sp. nov., general view, HBUMM 08298 - spec. 1, holotype D L. zhengpingliui Wu, sp. nov., general view, HBUMM 05553 - spec. 1, holotype E L. qingchuanensis Wu, sp. nov., general view, HBUMM 01179 - spec. 1, holotype F-H L. cheni Wu, sp. nov. F, G HBUMM 05553 b-spec. 1, holotype F general view G proximal penis H HBUMM 08428 - spec. 1, paratype, partial internal view of distal penis. Arrows indicate the position where two penial internal pilasters fuse into one distal pilaster.

Figure 48. SEM micrographs A, B Laeocathaica qishilii Wu, sp. nov., HBUMM 08298, paratype A protoconch B teleoconch C, D L. qiminglii Wu, sp. nov., HBUMM 08448, paratype C protoconch D teleoconch E, F L. phaeomphala Moellendorff, 1899, CZG 202008 - w 3, subadult E protoconch F teleoconch G, H L. filippina (Heude, 1882), HBUMM 04166 G protoconch H teleoconch I, J L. parapolytyla Wu, sp. nov., HBUMM 06640 - spec. 9, paratype I protoconch J teleoconch.

Figure 49. Habitats (excluding D) A, B Laeocathaica qishilii Wu, sp. nov., border of Jiuzhaigou County and Wen County C L. nordsiecki Wu, sp. nov., Guoyuanxiang, Jiuzhaigou D L. qiminglii Wu, sp. nov., an indoor photograph E L. qingchuanensis Wu, sp. nov., Dagou Nature Reserve, Qingchuan County F L. cheni Wu, sp. nov., Hengdan, Wenxian.