Abstract
This study revises the taxonomy of the genus Prismognathus Motschulsky, 1860 (Coleoptera: Lucanidae) endemic to Taiwan. To resolve nomenclatural ambiguity, the author designated a neotype for P. formosanus Nagel, 1928, whose type specimen has been lost. Morphological and distributional analysis confirmed that P. piluensis Sakaino, 1992 represents only intraspecific variation, leading to the new synonym: P. formosanus Nagel, 1928 = P. piluensis Sakaino, 1992, new synonymy. Furthermore, examination of the holotypes determined that P. davidis nigerrimus Sakaino & Yu, 1993 is a junior synonym of P. davidis cheni Bomans & Ratti, 1973, confirming that color polymorphism alone is insufficient for subspecific division. This revision clarifies the classification of Prismognathus in Taiwan.
References
- Bartolozzi, L., Sprecher-Uebersax, E. & Bezděk, A. (2016) Family Lucanidae Latreille, 1804. In: Löbl, I. & Löbl, D. (Eds.), Catalogue of Palaearctic Coleoptera. Vol. 3. Scarabaeoidea—Scirtoidea—Dascilloidea—Buprestoidea—Byrrhoidea. Revised and Updated Edition. Brill, Leiden and Boston, pp. 58–84.
- Bomans, H.E. & Ratti, P. (1973) Contribution à l‘étude des Coléoptères Lucanides. Description d‘une nouvelle sous-espèce de Taiwan (Formose). Bulletin et Annales de la Société Royale Belge d‘Entomologie, 109, 282–284.
- Chang, Y.J. (2006) Stag beetles 54. Yuan-Liou Publishing Company, Taipei, 160 pp. [in Chinese]
- Fujita, H. (2010) The lucanid beetles of the world. Mushi-sha’s Iconographic Series of Insects 6. Mushi-sha, Tokyo, 472 pp. [in Japanese]
- Gaedike, R. & Groll, E.K. (2001) Entomologen der Welt (Biographien, Sammlungsverbleib). Database. DEI Eberswalde im ZALF e.V. Available from: http://www.zalf.de/deie/biograph.phtml (accessed 24 November 2025)
- Huang, H. & Chen, C.C. (2012) A review of the genera Prismognathus Motschulsky and Cladophyllus Houlbert (Coleoptera: Scarabaeoidea: Lucanidae) from China, with the description of two new species. Zootaxa, 3255 (1), 1–36. https://doi.org/10.11646/zootaxa.3255.1.1
- Huang, H. & Chen, C.C. (2017) Stag Beetles of China III. Formosa Ecological Company, Taipei, 524 pp.
- Huang, H. & Chen, C.C. (2023) Revisional notes and new descriptions of stag beetles from China (Coleoptera: Lucanidae). Beetles World, 25, 7–37.
- International Commission on Zoological Nomenclature (1999) International Code of Zoological Nomenclature. 4th Edition. International Trust for Zoological Nomenclature, London, 306 pp.
- Mizunuma, T. & Nagai, S. (1994) The Lucanid beetles of the world. Mushi-sha‘s Iconographic Series of Insects 1. Mushi-sha, Tokyo, 1338 pp. [in Japanese]
- Nagel, P. (1928) Neues über Hirschkäfer. Deutsche Entomologische Zeitschrift, 1928, 273–298. https://doi.org/10.1002/mmnd.48019280402
- Sakaino, H. (1992) A new species of the genus Prismognathus from Taiwan. Gekkan-Mushi, 258, 10–12. [in Japanese]
- Sakaino, H. & Yu, C.K. (1993) Some notes on stag-beetles from Taiwan, with descriptions of two new subspecies. Gekkan-Mushi, 272, 14–16. [in Japanese]
- Tsai, C.L. & Yeh, W.B. (2016) Subspecific differentiation events of montane stag beetles (Coleoptera, Lucanidae) endemic to Formosa Island. PLoS ONE, 11 (6), e0156600. https://doi.org/10.1371/journal.pone.0156600
- Wang, C.B. & He, T.L. (2024) A new species of the genus Prismognathus Motschulsky (Coleoptera: Lucanidae) from Yunnan, China. The Indochina Entomologist, 1 (8), 53–59. https://doi.org/10.70590/ice.2024.01.08
- Weidner, H. (1976) Die Entomologischen Sammlungen des Zoologischen Instituts und Zoologischen Museums der Universität Hamburg, IX. Teil, Insecta VI. Mitteilungen aus dem Hamburgischen Zoologischen Museum und Institut, 73, 87–264.