Twenty-seven new species and four new genera of Gastropoda (Animalia: Mollusca) from plateau lake Quaternary sediments in Yunnan, southwestern China Author Xiang, Hong Quan 0009-0005-6737-3092 Yuxi Agriculture Vocation-Technical College Department of Animal Science, Xiangjiazhuang 41, Yanhe Street, Hongta District, Yuxi City, China. E-mail: 3044655033 @ qq. com; https: // orcid. org / 0009 - 0005 - 6737 - 3092 nnuchenhui@163.com Author Lu, Yi Zhi 0009-0005-6054-4952 Auburn University, Auburn, AL 36849, Alabama, United States of America. E-mail: yizhilu 698 @ gmail. com; https: // orcid. org / 0009 - 0005 - 6054 - 4952 Author He, Yue Ming 0009-0002-9849-7977 College of Engineering and Technology, Tianjin Agricultural University, Tianjin 300384, China. E-mail: 1123649307 @ qq. com; https: // orcid. org / 0009 - 0002 - 9849 - 7977 Author Li, Chong Ye Beijing Institute of Technology, Beijing 10008, China. E-mail: LCY 2395933264 @ 163. com; https: // orcid. org / 0009 - 0009 - 3279 - 139 X Author Gao, Han 0009-0007-8458-7222 Fuzhou University College of Computer and Data Science / College of Software, Fuzhou 350108, China. E-mail: boxcos @ foxmail. com; https: // orcid. org / 0009 - 0007 - 8458 - 7222 Author Lv, Ang Song 0009-0004-9908-0190 Kuang Wei Yu Memorial Middle School, Huadu District, Guangzhou 510800, China. E-mail: 3522450979 @ qq. com; https: // orcid. org / 0009 - 0004 - 9908 - 0190 Author Chen, Hui 0009-0004-5222-3975 School of Life Sciences, Nanchang University, Nanchang 330031, China. https: // orcid. org / 0009 - 0004 - 5222 - 3975 Corresponding authors. Hui Chen (E-mail: nnuchenhui @ 163. com), Hong Quan Xiang (E-mail: 3044655033 @ qq. com) nnuchenhui@163.com text Ecologica Montenegrina 2025 2025-04-16 84 48 71 https://doi.org/10.37828/em.2025.84.6 journal article 10.37828/em.2025.84.6 2336-9744 16960274 FCB98FB1-F97C-45AB-BFDF-E107D846C44D Paraprososthenia bicarinata Xiang, He, Lu & Chen , sp. nov. https://zoobank.org/ urn:lsid:zoobank.org:act: 27968859-1552-4BAC-903D-6652708AA905 Fig. 2 B , Fig. 3 D-E Material examined. Holotype : XHQ 24010201, shell height 17.0 mm. Yanjiang Town [ 沿江Dz ], Qilin District [ dzǝ区 ], Qujing City , Yunnan Province , China , 25.48°N , 103.87°E , June 2024 , collected by Yue-Ming He and Hong-Quan Xiang ( Fig. 1 ). Paratypes : 1 specimen , XHQ 24010202, shell height 15.0 mm, June 2024 , locality and habitat same as holotype . Diagnosis. Shell small, elongate conic, white, with eight whorls, the whorls with keels and axial ribs, aperture ovate, inner lip thickened, outer lip reflexed and thickened. Description. Shell small, but solid, elongate conic, white, with eight whorls, including two protoconch whorls; third to fifth whorls with two very week keels and shell surface smooth; sixth whorls with two week keels and very week axial ribs; other whorls with two very obvious keels and week axial ribs; body whorls not swollen. Shell surface with axial growth lines. Apex obtuse. Umbilicus narrow and small, base with one keel around umbilical area. Aperture ovate, inner lip thickened and smooth; outer lip thickened and reflexed. Differential diagnosis. Compared with P. costata and P. constricta , Paraprososthenia bicarinata sp. nov. shell surface lacks nodules and with two very obvious keels. Compared to Parapyrgula coggini and Paraprososthenia gredleri , Paraprososthenia bicarinata sp. nov. shell is larger, surface with week axial ribs. Compared with P. bronyaae sp. nov. , Paraprososthenia bicarinata sp. nov. shell surface with week axial ribs and less whorls. Etymology. The species name " bicarinata " originates from the characteristic of having two keels on the whorls. We suggest the Chinese common name as " uAEḄ川ϐ ". Distribution and ecology. This species is only found in the lake sediments of Qilin District, Yunnan Province .