Taxonomic Validity of Hynobius Hidamontanus (Caudata: Hynobiidae): Descriptions of Four New Species from Western Honshu, Japan

Hirotaka Sugawara¹, Takayuki Iwata², Jun-ichi Naito³, Masaru Yamada⁴, Kazuto Onomura⁵ and Masahiro Nagano^6,

¹Faculty of Science and Technology, Kochi University, Akebonocho 2-5-1, Kochi City, Kochi Prefecture, 780-8520, Japan

²Yasugi City Hall, Yasugicho 878-2, Yasugi City, Shimane Prefecture, 692-8686, Japan

³Wildlife Conservation Promotor of Hiroshima Prefecture, Motomachi 10-52, Naka Ward, Hiroshima City, Hiroshima Prefecture, 730-8511, Japan

⁴Nature Conservation Promotor of Okayama Prefecture, Daiku 1-2-3, Kita Ward, Okayama City, Okayama Prefecture, 700-8554, Japan

⁵Independent Researcher, Ato-kanekami 3441-1, Yamaguchi City, Yamaguchi Prefecture, 759-1601, Japan

⁶Faculty of Science and Technology, Oita University, Dannoharu 700, Oita City, Oita Prefecture, 870-1192, Japan

Cite this paper:
Hirotaka Sugawara, Takayuki Iwata, Jun-ichi Naito, Masaru Yamada, Kazuto Onomura and Masahiro Nagano. Taxonomic Validity of Hynobius Hidamontanus (Caudata: Hynobiidae): Descriptions of Four New Species from Western Honshu, Japan. American Journal of Zoological Research. 2023; 8(1):6-26. doi: 10.12691/ajzr-8-1-2

Abstract

Four new species of Hynobius are described from the Chugoku Mountains, Japan. The complex of Hynobius utsunomiyaorum, including Hynobius hidamontanus, was divided into six groups based on morphological and molecular analyses. The Mt. Sanbe and Kitahiroshima, Mt. Mengame, northern central Okayama, and northeastern Okayama groups of H. utsunomiyaorum were described as Hynobius pseudoutsunomiyaorum sp. nov., Hynobius mengamemontanus sp. nov., Hynobius sakuhokumontanus sp. nov., and Hynobius ushiromontanus sp. nov., respectively. Molecular analyses of samples from across the entire distribution range of H. utsunomiyaorum revealed that H. utsunomiyaorum (including H. hidamontanus) has six genetic groups. Morphological analyses suggested that males of the four new species are morphologically different from H. utsunomiyaorum according to specific characters. The distribution of the new species, as well as those of H. utsunomiyaorum and H. hidamontanus, were determined and compared to indicate the isolation among the species. Although further sampling from the northern part of Okayama Prefecture is needed to determine the distribution ranges of H. utsunomiyaorum and H. sakuhokumontanus sp. nov., our results suggest that the distribution area of true H. utsunomiyaorum is mainly limited to the central area of the Chugoku Mountains.

Keywords:
Chugoku Mountains conservation cryptic species geographic isolation Hokuriku District mitochondrial DNA

This work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

Figures

References:

[1]	Frost, D.R., Amphibian Species of the World 6.2, an Online Reference. American Museum of Natural History, New York, 2023. Available: https://amphibiansoftheworld.amnh.org/Amphibia/Caudata/Hynobiidae/Hynobiinae/Hynobius (accessed on 5 September 2023).
[2]	Sato, I. “On a new species of Hynobius from Japan” Journal of Science of the Hiroshima University, Series B, Division 1, Zoology, 3, 1-25, 1934.
[3]	Sato, I. “Regarding salamanders from Oki” Zoological Magazine, 52, 298-309. 1940. (In Japanese).
[4]	Sugawara, H., Watabe, T., Yoshikawa, T. and Nagano, M. “Morphological and molecular analyses of Hynobius dunni reveal a new species from Shikoku, Japan” Herpetologica, 74, 159-168. 2018.
[5]	Nishikawa, K. and Matsui, M. “Three new species of the salamander genus Hynobius (Amphibia, Urodela, Hynobiidae) from Kyushu, Japan” Zootaxa 3852, 203-226, 2014.
[6]	Matsui, M., Misawa, Y., Nishikawa, K. and Shimada, T. “A new species of lentic breeding salamander (Amphibia, Caudata) from central Japan” Current Herpetology, 36, 116-126, 2017.
[7]	Matsui, M., Okawa, H., Nishikawa, K., Aoki, G., Eto, K., Yoshikawa, N., Tanabe, S., Misawa, Y. and Tominaga, A. “Systematics of the widely distributed Japanese clouded salamander, Hynobius nebulosus (Amphibia: Caudata: Hynobiidae), and its closest relatives” Current Herpetology, 38, 32-90, 2019.
[8]	Matsui, M. “Isozyme variation in salamanders of the nebulosus-lichenatus complex of the genus Hynobius from eastern Honshu, Japan, with a description of a new species” Japanese Journal of Herpetology, 12, 50-64, 1987.
[9]	Sawada, K., Kusama, S., Kameya, M. and Nakada, T. “Inhabitation of Hynobius hidamontanus in a region of the southern part of Toyama Prefecture” Amphibian History, (33), 8-15, 2021. (In Japanese).
[10]	Sugawara, H., Iwata, T., Yamashita, H. and Nagano, M. “Taxonomic reassessment of the Izumo Lineage of Hynobius utsunomiyaorum: description of a new species from Chugoku, Japan” Animals, 11, 2187, 2021.
[11]	Frost, D.R. and Hillis, D.M. “Species in concept and practice: herpetological applications” Herpetologica, 46, 87-104, 1990.
[12]	Dubois, A. “The International Code of Zoological Nomenclature must be drastically improved before it is too late” Bionomina, 2, 1-104, 2011.
[13]	Hayashi, M. and Ooi, K. “Molecular study on Hynobius in east area of Shimane Prefecture, Japan: notes on haplotype diversity of mtDNA and their distribution” Bulletin of the Hoshizaki Green Foundation, 23, 99-104, 2020. (in Japanese).
[14]	Matsui, M., Tominaga, A., Hayashi, T., Misawa, Y. and Tanabe, S. “Phylogenetic relationship and phylogeography of Hynobius tokyoensis (Amphibia: Caudata) using complete sequences of cytochrome b and control reason genes of mitochondrial DNA” Molecular Phylogenetics and Evolution, 44, 204-216, 2007.
[15]	Kumar, S., Stecher, G., Li, M., Knyaz, C. and Tamura, K. “MEGA X: molecular evolutionary genetics analysis across computing platforms” Molecular Biology and Evolution, 35, 1547-1549, 2018.
[16]	Schwarz, G. “Estimating the dimension of a model” Annals of Statistics, 6, 461-464, 1978.
[17]	Sugiura, N. “Further analyses of the data by akaike's information criterion and the finite corrections” Communications in Statistics - Theory and Methods, 7, 13-26, 1978.
[18]	Darriba, D., Taboada, G.L., Doallo, R. and Posada, D. “jModelTest 2: more models, new heuristics and parallel computing” Nature Methods, 9, 772, 2012.
[19]	Ronquist, F., Teslenko, M., van der Mark, P., Ayres, D.L., Darling, A., Höhna, S., Larget, B., Liu, L., Suchard, M.A. and Huelsenbeck, J.P. “MrBayes 3.2: efficient Bayesian phylogenetic inference and model choice across a large model space” Systematic Biology, 61, 539-542, 2012.
[20]	Huelsenbeck, J.P and Rannala, B. “Frequentist properties of Bayesian posterior probabilities of phylogenetic trees under simple and complex substitution models” Systematic Biology, 53, 904-913, 2004.
[21]	Hillis, D.M and Bull, J.J. “An empirical test of bootstrapping as a method for assessing confidence in phylogenetic analysis” Systematic Biology, 42, 182-192, 1993.
[22]	Bennett, R.A. “A review of anesthesia and chemical restraint in reptiles” Journal of Zoo and Wildlife Medicine, 22, 282-303, 1991.
[23]	Nishikawa, K., Matsui, M., Tanabe, S. and Sato, S. Morphological and allozymic variation in Hynobius boulengeri and H. stejnegeri (Amphibia: Urodela: Hynobiidae). Zoological Science, 24, 752-766, 2007.
[24]	Ihaka, R. and Gentleman, R. “R: a language for data analysis and graphics” Journal of Computational and Graphical Statistics, 5, 299-314, 1996.
[25]	Sugawara, H., Naito, J., Iwata, T. and Nagano, M. “Molecular phylogenetic and morphological problems of the Aki salamander Hynobius akiensis: description of two new species from Chugoku, Japan” Bulletin of the Kanagawa Prefectural Museum (Natural Science), (51), 35-46, 2022.
[26]	Okamiya, H., Sugawara, H., Nagano, M. and Poyarkov, N.A. “An integrative taxonomic analysis reveals a new species of lotic Hynobius salamander from Japan” PeerJ, 6, e5084, 2018.
[27]	Tominaga, A., Matsui, M. and Nishikawa, K. “Two new species of lotic breeding salamanders (Amphibia, Caudata, Hynobiidae) from western Japan” Zootaxa, 4550, 525-544, 2019.
[28]	Okawa, H., Utsunomiya, T., Utsunomiya, Y. and Naito, J. “Hynobius nebulosus from Hiroshima Prefecture” Hibakagaku, 146, 49-53, 1990. (In Japanese).
[29]	Okada, S. (2022). Hiba Salamander In: Red Data Book Tottori, Third Edition, 2022, Tottori Prefecture, Japan, 2022, 72. Available: https://www.pref.tottori.lg.jp/secure/1308351/B53amprept.pdf (accessed on 5 September 2023). (in Japanese).
[30]	Okawa, H., Okuno, T. and Utsunomiya, T. “Major groups of Hynobius nebulosus in western Japan” Bulletin of the Herpetological Society of Japan, 2019, 9-21, 2019. (In Japanese).
[31]	Okawa, H. and Iwata, T. “Problems on the highland-type of Hynobius nebulosus” Proceedings of the Kyushu Herpetological Society, (6), 43-46, 2015. (In Japanese).
[32]	Matsui, M., Nishikawa, K., Utsunomiya, T. and Tanabe, S. “Geographic allozyme variation in the Japanese clouded salamander, Hynobius nebulosus (Amphibia: Urodela)” Biological Journal of the Linnean Society, 89, 311-330, 2006.
[33]	Matsui, M., Misawa, Y., Yoshikawa, N. and Nishikawa, K. “Taxonomic reappraisal of Hynobius tokyoensis, with description of a new species from northeastern Honshu, Japan (Amphibia: Caudata)” Zootaxa, 5168, 207-221, 2022.
[34]	Tominaga, A., Matsui, M., Tanabe, S. and Nishikawa, K. “A revision of Hynobius stejnegeri, a lotic breeding salamander from western Japan, with a description of three new species (Amphibia, Caudata, Hynobiidae)” Zootaxa, 4651, 401-431, 2019.
[35]	Nambu, H. “Hynobius tenuis (Caudata, Hynobiidae), a new species of salamander from central Japan” Zoological Science, 8, 991-997, 1991.
[36]	Matsui, M., Nishikawa, K., Misawa, Y., Kakegawa, M. and Sugahara, T. “Taxonomic relationships of an endangered Japanese salamander Hynobius hidamontanus Matsui, 1987 with H. tenuis Nambu, 1991 (Amphibia: Caudata)” Current Herpetology, 21, 25-34, 2002.
[37]	Horiike, T. “An introduction to molecular phylogenetic analysis” Reviews in Agricultural Science, 4, 36-45, 2016.
[38]	Sparreboom, M. Salamanders of the Old World, KNNV Publishing, Zeist, Netherland, 2014, 51-102.
[39]	Ministry of the Environment. (2020). Red Data Book and Red List, 2020, Ministry of Environment, Japan. Available: https://ikilog.biodic.go.jp/Rdb/booklist (accessed on 5 September 2023). (in Japanese).