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Issue: Vol. 5785 No. 1: 27 Mar. 2026
Type: Article
Published: 2026-03-27
DOI: 10.11646/zootaxa.5785.1.5
Page range: 134-151
Abstract views: 36
PDF downloaded: 0

Rediscovery and redescription of an endemic land snail from Vietnam: Cyclotus simonianus (Heude, 1886) with its phylogenetic position

Center for Biodiversity Conservation and Endangered Species (CBES); 541 Nguyen Duy Trinh; Binh Trung Ward; Ho Chi Minh City; Vietnam.
Faculty of Biology; University of Education; Hue University; 34 Le Loi Street; Hue City; Vietnam.
Center for Biodiversity Conservation and Endangered Species (CBES); 541 Nguyen Duy Trinh; Binh Trung Ward; Ho Chi Minh City; Vietnam.
Institute of Advanced Technology; Vietnam Academy of Science and Technology; Ho Chi Minh City; Vietnam.
Faculty of Biology and Biotechnology; Ho Chi Minh City University of Science; Vietnam National University; Ho Chi Minh City; Vietnam.
HUN-REN Centre for Agricultural Research; 2462 Martonvásár; Brunszvik u. 2.; Hungary.; Department of Soil; Water and Natural Sciences; Albert Kázmér Faculty of Agricultural and Food Sciences of Széchenyi István University; Vár 2.; 9200 Mosonmagyaróvár; Hungary.
Mollusca Cyclotus Opisthoporus land snail phylogenetic Vietnam Ba Den Mountain

Abstract

Since its original description in 1886, Cyclotus simonianus (Heude, 1886) has remained poorly studied and its taxonomic status has not been critically reassessed. In this study, we rediscovered this species from Tay Ninh Province, southern Vietnam, and provide a detailed redescription based on new shell and anatomical characters. Molecular analyses based on COI sequences confirm its placement within the genus Cyclotus Swainson 1840, although relationships within the genus remain unresolved due to limited comparative data. Based on morphological evidence, we consider Rhiostoma tieni Thach, 2024 to be a junior synonym of C. simonianus.

 

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How to Cite

Tran, T.G., Bui, C.T., Vu, L., Le, D.K.T., Ho, H.N.V. & Páll-Gergely, B. (2026) Rediscovery and redescription of an endemic land snail from Vietnam: Cyclotus simonianus (Heude, 1886) with its phylogenetic position. Zootaxa, 5785 (1), 134–151. https://doi.org/10.11646/zootaxa.5785.1.5