Miraphaedusa xihuashida Chen 2025, sp. nov.

Miraphaedusa xihuashida Chen sp. nov. Materials Type status: Holotype. Occurrence: individualID: NCUMB 2507007; individualCount: 1; occurrenceID: F8F0D039-959A-5C70-A400-54F1BCC33D3A; Taxon: kingdom: Animalia; phylum: Mollusca; class: Gastropoda; order: stylommatophora; family: Clausiliidae; genus: Miraphaedusa; Location: country: China; stateProvince: Guizhou; municipality: Tongren; locality: Tongren Grand Canyon [铜仁大峡谷]; verbatimLatitude: 27.8825°N; verbatimLongitude: 109.2494°E; Identification: identifiedBy: Z.-G. Chen; Event: eventDate: June 2025; Record Level: institutionID: Museum of Biology, Nanchang University Type status: Paratype. Occurrence: individualID: NCUMB 2507008–10; individualCount: 3; occurrenceID: 54EA104A-D052-50A1-9DB6-B2CB0840AD6F; Taxon: kingdom: Animalia; phylum: Mollusca; class: Gastropoda; order: stylommatophora; family: Clausiliidae; genus: Miraphaedusa; Location: country: China; stateProvince: Guizhou; municipality: Tongren; locality: Tongren Grand Canyon [铜仁大峡谷]; verbatimLatitude: 27.8825°N; verbatimLongitude: 109.2494°E; Identification: identifiedBy: Z.-G. Chen; Event: eventDate: June 2025; Record Level: institutionID: Museum of Biology, Nanchang University Type status: Paratype. Occurrence: individualID: ZMNH AIMS 29006; individualCount: 1; occurrenceID: 2D396C96-D3B0-5BC9-8DA5-3F646A888B51; Taxon: kingdom: Animalia; phylum: Mollusca; class: Gastropoda; order: stylommatophora; family: Clausiliidae; genus: Miraphaedusa; Location: country: China; stateProvince: Guizhou; municipality: Tongren; locality: Tongren Grand Canyon [铜仁大峡谷]; verbatimLatitude: 27.8825°N; verbatimLongitude: 109.2494°E; Identification: identifiedBy: Z.-G. Chen; Event: eventDate: June 2025; Record Level: institutionID: Zhejiang Museum of Natural History Type status: Paratype. Occurrence: individualID: SZ 25062506; individualCount: 2; occurrenceID: F1D3F180-D54D-5B3E-8902-6237E785E436; Taxon: kingdom: Animalia; phylum: Mollusca; class: Gastropoda; order: stylommatophora; family: Clausiliidae; genus: Miraphaedusa; Location: country: China; stateProvince: Guizhou; municipality: Tongren; locality: Tongren Grand Canyon [铜仁大峡谷]; verbatimLatitude: 27.8825°N; verbatimLongitude: 109.2494°E; Identification: identifiedBy: Z.-G. Chen; Event: eventDate: June 2025; Record Level: institutionID: Collection of Miklós Szekeres Description Shell (Fig. 1 a). Shell fusiform, sinistral, thick-walled, solid, reddish-brown, with 10.5–12.25 whorls. Whorls have an opaque surface with thin and dense growth lines. Apical part thick. Aperture projected, narrow, oblong. Peristome strongly doubled, thick, expanded and reflexed, with or without indistinct palatal serration. Superior lamella strong, highest at the position near its outer end, extending to the peristome margin. Weak inferior and subcolumellar lamella closely positioned, the former descending to near to the peristome margin and the latter to the peristome margin. Principal plica long, initiates ventrally and ends near the aperture. Palatal plicae 4–5, short, lateral, nearly straight or slightly curved. Clausilium plate invisible through the aperture in oblique view. Measurements: holotype, shell height 27.5 mm, shell width 6.2 mm, aperture height 6.2 mm, aperture width 4.8 mm; paratypes, shell height 24.7–26.8 mm, shell width 5.8–6.2 mm, aperture height 5.8–6.2 mm, aperture width 4.4–4.7 mm. Genitalia (Fig. 2). Atrium short and thin. Penis, cylindrical, gradually thickening distally, becoming narrower shortly before the transition to epiphallus. Penial caecum present. Epiphallus thick, shorter than penis. Penial retractor long and thick, inserted at the middle part of epiphallus. Vas deferens relatively thin and short. Vagina thick, cylindrical, longer than free oviduct. Basal part of diverticulum thick, thinning to apical part and attached to spermoviduct. Spermoviduct thick and long. Pedunculus of bursa copulatrix slender and long. Bursa copulatrix large, oblong. Diagnosis Shell fusiform, thick, solid, opaque, reddish-brown, height 24.7–27.5 mm, with 10.5–12.25 whorls. Peristome strongly doubled, thick, expanded and reflected, with or without indistinct palatal serration. Inferior and subcolumellar lamella close and weak, the former descending to near the peristome margin and the latter descending to the peristome margin. Palatal plicae 4–5, short, lateral, nearly straight or slightly curved. The new species can be easily distinguished from M. takagii and M. pretiosa by the fusiform shell (vs. slender). It is similar to M. gregoi by the similar shell shape, but differs by the larger shell (shell height 24.7–27.5 mm vs. 15.6–18.9 mm), the stronger first peristome, the stronger subcolumellar lamella and the closer position of the two peristome margins (Fig. 1). Etymology The specific name is made from the Pīnyīn form for China West Normal University, the alma mater of the first author. Next year will be the 80 th anniversary of the university's founding and the first author wishes to commemorate this with the species name. The vernacular name is 西华师大奇管螺 (Pīnyīn: xī huá shī dà qí guǎn luó). Distribution Known from the type locality only (Fig. 3). Ecology Living animals were found under fallen leaves in dense shrubs together with Cyclophorus sp. and Bradybaena sp. Taxon discussion Nordsieck (2012 a) treated the monotypic genus Falsiluna Grego & Szekeres, 2011 as a subgenus of Miraphaedusa. Subsequently, Hunyadi and Szekeres (2016) restored the independence of Falsiluna. Falsiluna harryleei Grego & Szekeres, 2011, the only species of of its genus, has dextral shell with lunella-like palatal plicae, which strongly differ from those of Miraphaedusa. Therefore, we treat Falsiluna as an independent genus, while Miraphaedusa contains only three species and M. xihuashida Chen sp. nov. The new species occurs in north-eastern Guizhou, far away from the localities of its congeners (Fig. 3).