Curriculum Vitaes

Hidetoshi Ota

  (太田 英利)

Profile Information

Affiliation
Professor, Institute of Natural and Environmental Sciences, University of Hyogo
Degree
Master of Science(Kyoto University)
Ph. D.(Kyoto University)

Other name(s) (e.g. nickname)
Toshi
J-GLOBAL ID
200901063298720728
researchmap Member ID
1000047308

Papers

 313
  • Matsuda, Y, Kaburagi, S, Kamezaki, N, Ota, H, Takahashi,H, Imazu, T, Kagayama, S, Kawamura, K
    Zoological Journal of the Linnean Society, 1-11, Jun 1, 2024  Peer-reviewed
  • Nana Watanabe, Kohsaku Arai, Makoto Otsubo, Mamoru Toda, Atsushi Tominaga, Shun Chiyonobu, Tokiyuki Sato, Tadahiro Ikeda, Akio Takahashi, Hidetoshi Ota, Yasufumi Iryu
    Progress in Earth and Planetary Science, 10(1) 1-30, Jul 20, 2023  Peer-reviewed
    Abstract The modern and Late Pleistocene terrestrial fauna of Miyako Jima and adjacent islands (the Miyako Islands) in the southern Ryukyu Islands, southwestern Japan, includes some endemic taxa or genetically unique populations that exclusively have closest allies in the more isolated Okinawa Jima and adjacent islands (the Okinawa Islands) than in the Yaeyama Islands, which are located southwest of the Miyako Islands with much narrower intervening straits. Those taxa or populations include representatives of lineages that have physiologically highly limited ability for over-sea dispersal and the Miyako Islands are currently separated from the Okinawa Islands by at least 300 km of open water; therefore, the formation of this phylogeographical pattern is perplexing. In this study, we review the late Cenozoic geology of the Miyako Islands, southern Okinawa Jima, the Okinawa–Miyako submarine plateau (OMSP; a plateau located between Okinawa Jima and Miyako Jima), and the Kerama gap, which is a depression between the OMSP and Okinawa Jima. We then consider the origin of the modern and Late Pleistocene terrestrial animals, including a number of non-volant vertebrates on the Miyako Islands. Finally, we propose a new hypothesis (the OMSP hypothesis) to explain the enigmatic composition of modern and Late Pleistocene terrestrial vertebrate fauna of the islands. Southern Okinawa Jima was uplifted and emerged after ca. 2 Ma and was temporarily connected to the OMSP, which is likely to have emerged earlier than southern Okinawa Jima, to form a large island extending from Okinawa Jima to the Miyako Islands with a NE–SW direction of ~ 400 km. Subsequently, Okinawa Jima became separated from the OMSP when the Ryukyu Group—which is composed of Quaternary reef and associated fore-reef and shelf deposits—began to accumulate around the island at 1.7–1.4 Ma. During the interval from 2.0 to 1.7–1.4 Ma, numerous terrestrial animals, including flightless vertebrates, extended their distribution to the OMSP. Although the Miyako Islands repeatedly underwent complete submergence during deposition of the main part of the Ryukyu Group (1.25–0.4 Ma), they were uplifted and emerged to become a land area after ca. 0.4 Ma. In contrast, the OMSP subsided after ca. 0.4 Ma and was almost completely submerged after 0.27 Ma. During ca. 0.4–0.27 Ma, terrestrial animals migrated from the OMSP to the Miyako Islands.
  • Xiakena Xiaokaiti, Yasuyuki Hashiguchi, Hidetoshi Ota, Yoshinori Kumazawa
    Genes, 13(8) 1470-1470, Aug 17, 2022  Peer-reviewed
    Mitochondrial genomes of four elapid snakes (three marine species [Emydocephalus ijimae, Hydrophis ornatus, and Hydrophis melanocephalus], and one terrestrial species [Sinomicrurus japonicus]) were completely sequenced by a combination of Sanger sequencing, next-generation sequencing and Nanopore sequencing. Nanopore sequencing was especially effective in accurately reading through long tandem repeats in these genomes. This led us to show that major noncoding regions in the mitochondrial genomes of those three sea snakes contain considerably long tandem duplications, unlike the mitochondrial genomes previously reported for same and other sea snake species. We also found a transposition of the light-strand replication origin within a tRNA gene cluster for the three sea snakes. This change can be explained by the Tandem Duplication—Random Loss model, which was further supported by remnant intervening sequences between tRNA genes. Mitochondrial genomes of true snakes (Alethinophidia) have been shown to contain duplicate major noncoding regions, each of which includes the control region necessary for regulating the heavy-strand replication and transcription from both strands. However, the control region completely disappeared from one of the two major noncoding regions for two Hydrophis sea snakes, posing evolutionary questions on the roles of duplicate control regions in snake mitochondrial genomes. The timing and molecular mechanisms for these changes are discussed based on the elapid phylogeny.
  • Masaharu Motokawa, Tomohisa Makino, Takashi O. Yato, Shinya Okabe, Tsunehiro Shiroma, Masanao Toyama, Hidetoshi Ota
    Mammal Study, 47(3) 205-212, May 2, 2022  Peer-reviewedLast author
  • YUKI KOIZUMI, HIDETOSHI OTA, TSUTOMU HIKIDA
    Zootaxa, 5128(1) 61-83, Apr 19, 2022  Peer-reviewed
    We performed a molecular phylogenetic analysis for the ground skink populations of the genus Scincella Mittleman, 1950 on Yonagunijima Island, Southern Ryukyus and representative samples of Scincella species known from other islands of the East Asian Archipelago. Partial mitochondrial cytochrome c oxidase subunit I and cytochrome b sequence data were used. Additionally, we examined the nuclear genetic variation between the Yonagunijima samples and those of closely related species. The genetic distances were largely equivalent between the Yonagunijima population and the two closest species, S. boettgeri from other southern Ryukyu Islands and S. formosensis from Taiwan. Moreover, there were nuclear haplotypes unique to the Yonagunijima population. We thus recognize the Yonagunijima population as a distinct species and describe it as Scincella dunan sp. nov. Morphologically, S. dunan sp. nov. is similar to S. boettgeri, but differs in some morphometric and meristic characters, and dorsolateral stripe pattern. These findings further support the biogeographically unique status of Yonagunijima Island among the southern Ryukyus islands.
  • Chiaki Kambayashi, Ryosuke Kakehashi, Yusuke Sato, Hideaki Mizuno, Hideyuki Tanabe, Andolalao Rakotoarison, Sven Künzel, Nobuaki Furuno, Kazuhiko Ohshima, Yoshinori Kumazawa, Zoltán T. Nagy, Akira Mori, Allen Allison, Stephen C. Donnellan, Hidetoshi Ota, Masaki Hoso, Tetsuya Yanagida, Hiroshi Sato, Miguel Vences, Atsushi Kurabayashi
    Molecular Biology and Evolution, 39(4), Apr 10, 2022  Peer-reviewed
    Abstract Horizontal transfer (HT) of genes between multicellular animals, once thought to be extremely rare, is being more commonly detected, but its global geographic trend and transfer mechanism have not been investigated. We discovered a unique HT pattern of Bovine-B (BovB) LINE retrotransposons in vertebrates, with a bizarre transfer direction from predators (snakes) to their prey (frogs). At least 54 instances of BovB HT were detected, which we estimate to have occurred across time between 85 and 1.3 Ma. Using comprehensive transcontinental sampling, our study demonstrates that BovB HT is highly prevalent in one geographical region, Madagascar, suggesting important regional differences in the occurrence of HTs. We discovered parasite vectors that may plausibly transmit BovB and found that the proportion of BovB-positive parasites is also high in Madagascar where BovB thus might be physically transported by parasites to diverse vertebrates, potentially including humans. Remarkably, in two frog lineages, BovB HT occurred after migration from a non-HT area (Africa) to the HT hotspot (Madagascar). These results provide a novel perspective on how the prevalence of parasites influences the occurrence of HT in a region, similar to pathogens and their vectors in some endemic diseases.
  • Tadahiro Ikeda, Hidetoshi Ota, Tomonori Tanaka, Kenji Ikuno, Katsuhiro Kubota, Kohei Tanaka, Haruo Saegusa
    Cretaceous Research, 130 105063-1-105063-10, Feb, 2022  Peer-reviewed
  • Utpal Smart, Matthew J. Ingrasci, Goutam C. Sarker, Hmartlawmte Lalremsanga, Robert W. Murphy, Hidetoshi Ota, Ming Chung Tu, Yogesh Shouche, Nikolai L. Orlov, Eric N. Smith
    Journal of Zoological Systematics and Evolutionary Research, 59(8) 2212-2277, Nov 24, 2021  Peer-reviewed
  • Michael S Engel, Luis M P Ceríaco, Gimo M Daniel, Pablo M Dellapé, Ivan Löbl, Milen Marinov, Roberto E Reis, Mark T Young, Alain Dubois, Ishan Agarwal, Pablo Lehmann A., Mabel Alvarado, Nadir Alvarez, Franco Andreone, Katyuscia Araujo-Vieira, John S Ascher, Délio Baêta, Diego Baldo, Suzana A Bandeira, Phillip Barden, Diego A Barrasso, Leila Bendifallah, Flávio A Bockmann, Wolfgang Böhme, Art Borkent, Carlos R F Brandão, Stephen D Busack, Seth M Bybee, Alan Channing, Stylianos Chatzimanolis, Maarten J M Christenhusz, Jorge V Crisci, Guillermo D’elía, Luis M Da Costa, Steven R Davis, Carlos Alberto S De Lucena, Thierry Deuve, Sara Fernandes Elizalde, Julián Faivovich, Harith Farooq, Adam W Ferguson, Spartaco Gippoliti, Francisco M P Gonçalves, Victor H Gonzalez, Eli Greenbaum, Ismael A Hinojosa-Díaz, Ivan Ineich, Jianping Jiang, Sih Kahono, Adriano B Kury, Paulo H F Lucinda, John D Lynch, Valéry Malécot, Mariana P Marques, John W M Marris, Ryan C Mckellar, Luis F Mendes, Silvio S Nihei, Kanto Nishikawa, Annemarie Ohler, Victor G D Orrico, Hidetoshi Ota, Jorge Paiva, Diogo Parrinha, Olivier S G Pauwels, Martín O Pereyra, Lueji B Pestana, Paulo D P Pinheiro, Lorenzo Prendini, Jakub Prokop, Claus Rasmussen, Mark-Oliver Rödel, Miguel Trefaut Rodrigues, Sara M Rodríguez, Hearty Salatnaya, Íris Sampaio, Alba Sánchez-García, Mohamed A Shebl, Bruna S Santos, Mónica M Solórzano-Kraemer, Ana C A Sousa, Pavel Stoev, Pablo Teta, Jean-François Trape, Carmen Van-Dúnem Dos Santos, Karthikeyan Vasudevan, Cor J Vink, Gernot Vogel, Philipp Wagner, Torsten Wappler, Jessica L Ware, Sonja Wedmann, Chifundera Kusamba Zacharie
    Zoological Journal of the Linnean Society, 193(2) 381-387, Sep 24, 2021  Peer-reviewed
  • AWAL RIYANTO, MUHAMMAD ALIF FAUZI, IRVAN SIDIK, MUMPUNI, MOHAMMAD IRHAM, NIA KURNIAWAN, HIDETOSHI OTA, TAKU OKAMOTO, TSUTOMU HIKIDA, L. LEE GRISMER
    Zootaxa, 5026(2) 286-300, Aug 25, 2021  Peer-reviewed
    To reveal the diversity of Indonesian bent-toed geckos, we pay attention to Kalimantan (Borneo)—an island which has received less attention than other Indonesian islands such as Sumatra, Java, Sulawesi, the Moluccas, and the Lesser Sunda archipelagos. About 30 years after Hikida (1990) described three new Cyrtodactylus from Borneo, four more species were described, namely C. limajalur and C. muluensis in 2019, and C. hantu and C. miriensis in 2021, all by Davis et al. Through examination of the collection at MZB and three addition specimens collected from Tawau, we found several undescribed species, one of which we describe here. This new species is easily differentiated from all other congeners by the combination of the following characters: maximum SVL of at least 65.8 mm; no tubercles on dorsal surface of upper arm; tubercles present in the ventrolateral body folds; 28–30 paravertebral tubercles; 17–20 longitudinal dorsal tubercle rows; 39–46 ventral scale rows at midbody; 17–19 subdigital lamellae on fourth toe; precloacal pit with 5–7 pores in males arranged in a wide Λ-shape but absent in females; no enlarged transverse median subcaudals; paired dark brown semilunar-shaped markings on the upper nape. Further study is needed to reveal its molecular phylogenetic position and biogeographical history.
  • BENJAMIN R. KARIN, PAUL M. OLIVER, ALEXANDER L. STUBBS, UMILAELA ARIFIN, DJOKO T. ISKANDAR, EVY ARIDA, ZHENG OONG, JIMMY A. MCGUIRE, FRED KRAUS, MATTHEW K. FUJITA, IVAN INEICH, HIDETOSHI OTA, STACIE A. HATHAWAY, ROBERT N. FISHER
    Zootaxa, 4999(1) 87-100, Jul 8, 2021  Peer-reviewed
    The widespread parthenogenetic gecko Lepidodactylus lugubris is comprised of several clonal lineages, at least one of which has been known for some time to have originated from hybridization between its maternal ancestor, Lepidodactylus moestus, and a putatively undescribed paternal ancestor previously known only from remote islands in the Central Pacific. By integrating new genetic sequences from multiple studies on Lepidodactylus and incorporating new genetic sequences from previously sampled populations, we recovered a phylogenetic tree that shows a close genetic similarity between the generally hypothesized paternal hybrid ancestor and a recently described species from Maluku (Indonesia), Lepidodactylus pantai. Our results suggest that the paternal hybrid ancestor of at least one parthenogenetic clone of L. lugubris is conspecific with L. pantai and that the range of this species extends to Palau, the Caroline Islands, the Kei Islands, Wagabu, and potentially other small islands near New Guinea. Deeper genetic structure in the western (Palau, Maluku) versus eastern (eastern Melanesia, Micronesia, Polynesia) part of this species’ range suggests that the western populations likely dispersed via natural colonization, whereas the eastern populations may be the result of human-mediated dispersal. The potential taxonomic affinities and biogeographic history should be confirmed with further morphological and genetic analyses, including research on L. woodfordi from its type locality, which would have nomenclatural priority if found to be conspecific with L. pantai. We recommend referring to the wide-ranging sexual species as Lepidodactylus pantai until such a comparison can be made.
  • David G. Chapple, Uri Roll, Monika Böhm, Rocío Aguilar, Andrew P. Amey, Chris C. Austin, Marleen Baling, Anthony J. Barley, Michael F. Bates, Aaron M. Bauer, Daniel G. Blackburn, Phil Bowles, Rafe M. Brown, S.R. Chandramouli, Laurent Chirio, Hal Cogger, Guarino R. Colli, Werner Conradie, Patrick J. Couper, Mark A. Cowan, Michael D. Craig, Indraneil Das, Aniruddha Datta-Roy, Chris R. Dickman, Ryan J. Ellis, Aaron L. Fenner, Stewart Ford, S.R. Ganesh, Michael G. Gardner, Peter Geissler, Graeme R. Gillespie, Frank Glaw, Matthew J. Greenlees, Oliver W. Griffith, L. Lee Grismer, Margaret L. Haines, D. James Harris, S. Blair Hedges, Rod A. Hitchmough, Conrad J. Hoskin, Mark N. Hutchinson, Ivan Ineich, Jordi Janssen, Gregory R. Johnston, Benjamin R. Karin, J. Scott Keogh, Fred Kraus, Matthew LeBreton, Petros Lymberakis, Rafaqat Masroor, Peter J. McDonald, Sven Mecke, Jane Melville, Sabine Melzer, Damian R. Michael, Aurélien Miralles, Nicola J. Mitchell, Nicola J. Nelson, Truong Q. Nguyen, Cristiano de Campos Nogueira, Hidetoshi Ota, Panayiotis Pafilis, Olivier S.G. Pauwels, Ana Perera, Daniel Pincheira-Donoso, Robert N. Reed, Marco A. Ribeiro-Júnior, Julia L. Riley, Sara Rocha, Pamela L. Rutherford, Ross A. Sadlier, Boaz Shacham, Glenn M. Shea, Richard Shine, Alex Slavenko, Adam Stow, Joanna Sumner, Oliver J.S. Tallowin, Roy Teale, Omar Torres-Carvajal, Jean-Francois Trape, Peter Uetz, Kanishka D.B. Ukuwela, Leonie Valentine, James U. Van Dyke, Dylan van Winkel, Raquel Vasconcelos, Miguel Vences, Philipp Wagner, Erik Wapstra, Geoffrey M. While, Martin J. Whiting, Camilla M. Whittington, Steve Wilson, Thomas Ziegler, Reid Tingley, Shai Meiri
    Biological Conservation, 257 109101-1-109101-12, May, 2021  Peer-reviewed
  • Hasegawa, H, Ota, H
    Tropical Natural History, 21(1) 209-217, Apr, 2021  Peer-reviewedLast author
  • Norihiro Kuraishi, Masafumi Matsui, Hidetoshi Ota, Koshiro Eto
    Zoological Science, 38(2) 112-121, Apr, 2021  Peer-reviewed
    Fauna of the Central Ryukyus includes a high percentage of endemic species, and Hallowell's tree frog Hyla hallowellii Thompson, 1912 is one of such elements, occurring in a total of eight islands in the Amami and Okinawa Island groups. Using samples representing all of these eight island populations, we studied variations in morphology, karyotype, allozyme, and mtDNA, to clarify the pattern of geographic differentiation of H. hallowellii and consider factors for its formation. We could not clearly discriminate one population from another in morphology, nor could we find any interpopulation difference in karyotype. From genetic analyses, using allozymes and cyt b, we found low overall differentiations among populations. However, the southern populations from Okinawajima and Yoronjima were genetically nearly identical with the northern Amamioshima population. From that group the geographically intermediate Tokunoshima and Kakeromajima populations showed prominent differentiations. These patterns of geographical differentiation greatly differ from those known in other amphibian species of the Central Ryukyus, and suggest that H. hallowellii has evolutionary history unique to the species.
  • Richmond, J, Ota, H, Grismer, L. L, Fisher, R. N
    Biological Journal of the Linnean Society, 132(1) 74-92, Feb, 2021  Peer-reviewed
  • D.-I. Kim, I.-K. Park, S.-Y. Bae, J. J. Fong, Y.-P. Zhang, S.-R. Li, H. Ota, D. Park
    Journal of Ecology and Environment, 44(1) 1-8, Apr, 2020  Peer-reviewed
  • Jong-Sun Kim, Jaejin Park, Jonathan J. Fong, Yong-Pu Zhang, Shu-Ran Li, Hidetoshi Ota, Sung-Hun Min, Mi-Sook Min, Daesik Park
    Mitochondrial DNA Part A, 31(3) 120-130, Mar 26, 2020  Peer-reviewed
  • Takeshi Igawa, Hirotaka Sugawara, Masanao Honda, Atsushi Tominaga, Shohei Oumi, Seiki Katsuren, Hidetoshi Ota, Masafumi Matsui, Masayuki Sumida
    Conservation Genetics, 21(1) 13-26, Feb 11, 2020  Peer-reviewed
  • Mori, A, Ota, H, Hirate, K
    In: H. B. Lillywhite and M. Martins. Islands and Snakes. Isolation and Adaptive Evolution. Oxford University Press, New York., 288-309, Aug, 2019  Peer-reviewedInvited
  • Atsushi Tominaga, Masafumi Matsui, Naoko Shimoji, Wichase Khonsue, Chi Shiun Wu, Mamoru Toda, Koshiro Eto, Kanto Nishikawa, Hidetoshi Ota
    Zoologica Scripta, 48(4) 440-453, Jul, 2019  Peer-reviewedLast author
    The Ryukyu Archipelago, located at the southwestern part of Japan, is known as a group of continental islands and harbours many endemic taxa, supposedly reflecting its fairly long isolation from the Eurasian continent, Taiwan and the Japanese main islands. Microhyla okinavensis has been known as an endemic member of the terrestrial fauna of this archipelago. Molecular phylogenetic analyses using samples from nearly all island populations of the species and representative samples of other east Asian congeneric species revealed that M. okinavensis consists of four distinct subclades, of which the Amami, Okinawa and Miyako subclades, though exhibiting distinct genetic differentiations from each other, formed a monophyletic group (clade A). The remaining Yaeyama subclade was exclusively sister to M. mixtura from inland China, forming another monophyletic group (clade B), rendering M. okinavensis in the current definition paraphyletic. These results, as well as estimated dates of divergence from related taxa, indicate that M. okinavensis actually includes more than one distinct species. The results indicate that M. okinavensis and M. mixtura are relict species with disjunct distributions which had been most probably caused by invasion of M. fissipes in intervening areas.
  • D.-I. Kim, I.-K. Park, H. Ota, J. J. Fong, J.-S. Kim, Y.-P. Zhang, S.-R. Li, W.-J. Choi, D. Park
    Journal of Ecology and Environment, 43(34) 1-9, May, 2019  Peer-reviewed
  • Kazumi Matsubara, Yoshinori Kumazawa, Hidetoshi Ota, Chizuko Nishida, Yoichi Matsuda
    Cytogenetic and Genome Research, 157(1-2) 98-106, Apr, 2019  Peer-reviewedInvited
    The suborder Serpentes is divided into 2 infraorders, Scolecophidia and Alethinophidia, which diverged at an early stage of snake diversification. In this study, we examined karyotypes of 4 scolecophidian species (<i>Letheobia simonii</i>, <i>Xerotyphlops vermicularis</i>, <i>Indotyphlops braminus</i>, and <i>Myriopholis macrorhyncha</i>) and performed FISH with 18S-28S rDNA as well as microchromosomal and Z chromosome-linked genes of <i>Elaphe quadrivirgata</i> (Alethinophidia) to investigate the karyotype evolution in the scolecophidian lineage. Diploid chromosome numbers of <i>X. vermicularis</i> and <i>L. simonii</i> were 30 (16 macrochromosomes and 14 microchromosomes) and 32 (16 macrochromosomes and 16 microchromosomes), respectively. The karyotype of a female <i>M. macrorhyncha</i> consisted of 15 macrochromosomes and 19 microchromosomes, including a heterochromatic microchromosome, indicating the presence of a heteromorphic chromosome pair. <i>E. quadrivirgata</i> Z-linked genes mapped to chromosome 4 of <i>M. macrorhyncha</i>, not to the heteromorphic pair. Therefore, <i>M. macrorhyncha</i> may have differentiated ZW sex chromosomes which are not homologous to those of <i>E. quadrivirgata</i>. One of the<i> E. quadrivirgata</i> microchromosomal genes mapped to the terminal region of chromosome 4q in <i>X. vermicularis</i>, suggesting that fusions between microchromosomes and macrochromosomes occurred in this species. rDNA was localized in different macrochromosomal pairs in the 2 diploid scolecophidian snakes examined here, whereas the gene location in a microchromosomal pair was conserved in 5 alethinophidian species examined. These results might imply the occurrence of chromosome fusions in the scolecophidian lineages. In<i> I. braminus</i>, a unique parthenogenetic snake with a triploid karyotype (21 macrochromosomes and 21 microchromosomes), morphological heteromorphisms were identified in chromosomes 1 and 7. Such heteromorphisms in 2 chromosomes were also observed in individuals from distant locations in the broad distribution range of this species, suggesting that the heteromorphisms were fixed in the genome at an early stage of its speciation.
  • D.-I. Kim, I.-K. Park, J.-S. Kim, H. Ota, W.-J. Choi, I.-H. Kim, D. Park
    Animal Cells and Systems, 23(1) 64-70, Apr, 2018  Peer-reviewed
  • Takuma Kaito, Hidetoshi Ota, Mamoru Toda
    JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, 55(2) 156-166, May, 2017  Peer-reviewed
    Sinomicrurus japonicus has a conspicuous colour pattern of longitudinal black stripes and transverse sets of black and white bands with an orange-reddish background colour. The pattern varies markedly among island populations, and thus, three subspecies have been recognized. We conducted molecular phylogenetic analyses on the island populations to clarify the evolutionary trajectory of such colour patterns and reevaluate the current classification accordingly. The results indicated relatively deep allopatric divergences within S. j. boettgeri, paraphyly of S. j. boettgeri against other two subspecies, and two independent derivations of S. j. takarai from boettgeri-like ancestors. Detailed morphological analyses revealed that variations in the boettgeri and takarai forms were more or less continuous and that differences between the two takarai populations were very small. From these results, we propose synonymizing S. j. takarai with S. j. boettgeri. Morphological differences between the genetically most distant populations of S. j. boettgeri were also small, whereas the japonicus form was distinct from the remainder. Considering the possible evolution of S. j. japonicus through peripheral isolation, we propose retention of these two subspecies. This study provides a basis for future work on the adaptive significance of geographic variation in the colour pattern of S. japonicus.
  • 加藤悟郎, 中島淳志, 保田昌宏, 岩本俊孝, 太田英利, 森田哲夫
    宮崎の自然と環境, (2) 41-45, Mar, 2017  
  • Kurita, T, Ota, H, Hikida, T
    Zootaxa, 4254(5) 520-536, Mar, 2017  Peer-reviewedCorresponding author
  • HASEGAWA Hideo, OTA Hidetoshi
    Current herpetology, 36(1) 1-10, 2017  Peer-reviewedLast author
    <p>Helminthological examination was made on 42 individuals of Polypedates leucomystax captured on Miyakojima of the Miyako Group, Ryukyu Archipelago, Japan. Eight species (one digenean, five nematodes, one acanthocephalan, and one oligochaete) were recognized, of which one nematode Strongyloides sp. characterized by the presence of an isthmus in the esophagus, seemed to have been newly adopted by P. leucomystax from herpetofaunal elements native to Miyakojima. Meanwhile, Raillietnema rhacophori and Allodero sp. were considered to have reached this island by accompanying P. leucomystax from the Central Ryukyus. Present specimens of R. rhacophori differed from conspecific specimens from the Okinawa Group and Malaysia in a few morphological characters, presumably as a result of bottlenecks through the host's dispersals involving a limited number of worms.</p>
  • Ikeda, T, Otsuka, H, Ota, H
    Herpetological Monographs, 30 143-156, Oct, 2016  Peer-reviewed
  • Saka Yoshikawa, Makiko Mimura, Shin Watanabe, Liang-Kong Lin, Hidetoshi Ota, Yasushi Mizoguchi
    ZOOLOGICAL SCIENCE, 33(5) 520-526, Oct, 2016  Peer-reviewed
    The Ryukyu wild boar (Sus scrofa riukiuanus) is an endemic, morphologically defined subspecies of the Eurasian wild boar (S. scrofa) found on five islands of the Ryukyu Archipelago (a group of small islands stretching from mainland Japan to Taiwan). Two hypothetical scenarios have been proposed regarding the origin of the current Ryukyu wild boar populations: 1) natural dispersal and 2) transportation and subsequent release by prehistoric humans. To test these two hypotheses, we compared the mitochondrial cytochrome b gene sequence (1140 base pairs) in 352 individual wild boar samples that included representatives of all five insular populations of the Ryukyu wild boar and populations of other conspecific subspecies in insular East and Southeast Asia and the Eurasian Continent. A total of 68 haplotypes were recognized, of which 12 were unique to the Ryukyu wild boar populations. The results of Bayesian phylogenetic analyses supported monophyly of the five Ryukyu populations (posterior probability value of 92), confirming the validity of the subspecies as a natural group. Coalescent analysis estimated the divergence times between the Ryukyu wild boar and the other conspecific subspecies as 144-465 thousand years ago (Kya), with a 95% HPD (highest posterior density) range of 51-837 Kya, and with no significant migration. Taking the broadly accepted date of initial human migration to the Ryukyus (no earlier than 50 Kya) into consideration, our results strongly suggest that the ancestral form of the Ryukyu wild boar first entered the Ryukyu Archipelago by natural dispersal prior to the arrival of prehistoric humans.
  • Patchara Danaisawadi, Takahiro Asami, Hidetoshi Ota, Chirasak Sutcharit, Somsak Panha
    SCIENTIFIC REPORTS, 6 23832,, Apr, 2016  Peer-reviewed
    Specialized predator-prey interactions can be a driving force for their coevolution. Southeast Asian snail-eating snakes (Pareas) have more teeth on the right mandible and specialize in predation on the clockwise-coiled (dextral) majority in shelled snails by soft-body extraction. Snails have countered the snakes' dextral-predation by recurrent coil reversal, which generates diverse counterclockwise-coiled (sinistral) prey where Pareas snakes live. However, whether the snake predator in turn evolves any response to prey reversal is unknown. We show that Pareas carinatus living with abundant sinistrals avoids approaching or striking at a sinistral that is more difficult and costly to handle than a dextral. Whenever it strikes, however, the snake succeeds in predation by handling dextral and sinistral prey in reverse. In contrast, P. iwasakii with little access to sinistrals on small peripheral islands attempts and frequently misses capturing a given sinistral. Prey-handedness recognition should be advantageous for right-handed snail-eating snakes where frequently encountering sinistrals. Under dextral-predation by Pareas snakes, adaptive fixation of a prey population for a reversal gene instantaneously generates a sinistral species because interchiral mating is rarely possible. The novel warning, instead of sheltering, effect of sinistrality benefitting both predators and prey could further accelerate single-gene ecological speciation by left-right reversal.
  • 岩本俊孝, 太田英利, 那須哲夫, 森田哲夫, 末吉豊文, 星野一三雄, 石橋葵, 武市知美, 加藤悟郎, 河野慎也, 貴島靖仁, 斉藤政美
    宮崎の自然と環境, 36-46, Mar, 2016  
  • Danaisawadi, P, Asami, T, Ota, H, Sutchari, C, Panha, S
    Tropical Natural History, 16(1) 21-31, Mar, 2016  Peer-reviewed
  • Ikeda, T, Ota, H, Matsui, M
    Cretaceous Research, 61(1) 108-123, Feb, 2016  Peer-reviewed
  • Srikulnath, K, Uno, Y, Nishida, C, Ota, H, Matsuda, Y
    PLoS ONE, 10(8) 1-19, Aug, 2015  Peer-reviewed
  • Patchara Danaisawadi, Takahiro Asami, Hidetoshi Ota, Chirasak Sutcharit, Somsak Panha
    JOURNAL OF ETHOLOGY, 33(3) 243-246, Aug, 2015  Peer-reviewed
    The snail-eating snake Pareas carinatus tilts its head and strikes leftward or rightward, successfully preying on both dextral and sinistral snails. Striking direction does not depend on prey size or coiling direction. Neither the time from striking until dropping of the shell nor the number of mandibular retractions during feeding was affected by the snake's striking direction or by the snail's coiling direction. Mandibular dentition was only slightly right-handed. Unlike previously studied congeneric species, which are more specialized for feeding on dextral snails, P. carinatus may prey on dextral and sinistral snails with similar efficiency.
  • Akio Takahashi, Hiroyuki Otsuka, Hidetoshi Ota
    CURRENT HERPETOLOGY, 34(2) 149-163, Aug, 2015  Peer-reviewedLast author
    A new extinct species of the genus Mauremys (Testudines: Geoemydidae) is described on the basis of three fossils from the late Pleistocene deposit of Tomori Amaga Cave on Miyakojima Island of the Miyako Island Group, Southern Ryukyus, Japan. Of these fossils, two (the anterior half of the plastron and the nuchal) were previously tentatively identified as Mauremys mutica, an extant species whose distribution is currently confined to the Yaeyama Island Group within the Ryukyus. The turtle represented by these two specimens and another, previously unreported material (left third peripheral) actually most resembles M. japonica from mainland Japan and the Northern Ryukyus, and M. yabei from the middle Pleistocene of mainland Japan. The fossil turtle however, differs from the other two in exhibiting a medial length of the entoplastron greater than the interhyoplastron in ventral view, and in having a longitudinal groove medial to the gulo-humeral sulcus on the epiplastron evident in dorsal view. The present finding strengthens endemicity of the recent terrestrial fauna of the Miyako Island Group.
  • Atsushi Tominaga, Masafumi Matsui, Koshiro Eto, Hidetoshi Ota
    ZOOLOGICAL SCIENCE, 32(3) 240-247, Jun, 2015  Peer-reviewedLast author
    To investigate geographic genetic structures and taxonomic relationships among isolated populations of Buergeria japonica, occurring very widely in various habitats of the Ryukyu Archipelago and Taiwan, we conducted phylogenetic and demographic analyses among individuals from various localities, representing their entire distributional ranges. Buergeria japonica is genetically greatly differentiated and comprises three major clades (the Southern Taiwan [ST] clade, the Northern Taiwan + Southern Ryukyu [NT/SR] clade, and the Central + Northern Ryukyu [CR/NR] clade), each of which seems to represent independent species. The first divergence in the species is estimated to have occurred in the middle to late Miocene in areas of current Taiwan, then eastern periphery of the Asian continent. Split of the ST and the remaining clades, and subsequent divergence between the NT/SR and the CR/NR clades in the latter, indicate consecutive south to north vicariant diversifications. However, these vicariances are not always associated with formation of significant barriers such as deep straits. Less but still prominently diverged subclades (the Amami + Tokara [AM/TK] and the Okinawa [ON] subclades) in the CR/NR clade were recognized in spite of the absence of an intervening deep strait. Contrariwise, individuals from Amami and Tokara Groups formed the AM/TK subclade in spite of the presence of the intervening Tokara Gap (a long-standing deep tectonic strait). Furthermore, in the AM/TK subclade, low but definite genetic divergence was found between the Northern Amami + Tokara (NAM/TK) lineage and the Southern Amami (SAM) lineage. Estimated divergence time and gene flow rate within the NAM/TK lineage indicate that this species reached northern Tokara from the south by overseas dispersal over the Tokara Gap long after its formation, but not by more recent artificial transportation. This overseas dispersal would have been facilitated by its more frequent occurrence around coastal habitats than other frogs.
  • A.G.J. Rhodin, H. Kaiser, P.P. van Dijk, W. Wüster, M. O’Shea, M. Archer, M. Auliya, L. Boitani, R. Bour, V. Clausnitzer, T. Contreras-MacBeath, B.I. Crother, J.M. Daza, C.A. Driscoll, O. Flores-Villela, J. Frazier, U. Fritz, A. Gardner, C. Gascon, A. Georges, F. Glaw, F.G. Grazziotin, C.P. Groves, G. Haszprunar, P. Havaš, J.M. Hero, M. Hoffmann, M.S. Hoogmoed, B.D. Horne, J.B. Iverson, M. Jäch, C.L. Jenkins, R.K.B. Jenkins, A.R. Kiester, J.S. Keogh, T.E. Lacher Jr, J.E. Lovich, L. Luiselli, D.L. Mahler, D. Mallon, R. Mas, R.W. Mcdiarmid, J. Measey, R.A. Mittermeier, S. Molur, V. Mossbrugger, R. Murphy, D. Naish, M. Niekisch, H. Ota, J.F. Parham, M.J. Parr, N.J. Pilcher, R.H. Pine, A.B. Rylands, J.G. Sanderson, J. Savage, W. Schleip, G.J. Scrocchi, H.B. Shaffer, E.N. Smith, R. Sprackland, S.N. Stuar, H. Vetter, L.J. Vi, T. Waller, G. Webb, E.O. Wilson, H. Zaher, S. Thomson
    Bulletin of Zoological Nomenclature, 72(1) 65-78, Feb, 2015  
  • Ikeda, T, Ota, H, Saegusa, H
    Journal of Vertebrate Paleontology, 35(1) e885032-1-e885032-5, Feb, 2015  Peer-reviewed
  • Hirohiko Takeuchi, Guang-Xiang Zhu, Li Ding, Yezhong Tang, Hidetoshi Ota, Akira Mori, Hong-Shink Oh, Tsutomu Hikida
    Current Herpetology, 33(2) 148-153, Aug 1, 2014  Peer-reviewed
    We investigated the phylogenetic status and pattern of geographic variation in Rhabdophis lateralis on the basis of samples from across continental China, southeastern Russia, and the Korean Peninsula. The results confirmed the monophyly of the species and also revealed its extremely low genetic divergence. The population genetic analyses suggested that such low intraspecific divergence may reflect recent rapid population growth from a small ancestral population, extensive gene flow, or both. We conclude that R. lateralis is a good species, as suggested by our previous study, which analyzed fewer continental samples from a more limited range.
  • Cameron D. Siler, Jamie R. Oaks, Kerry Cobb, Hidetoshi Ota, Rafe M. Brown
    DIVERSITY AND DISTRIBUTIONS, 20(7) 756-772, Jul, 2014  Peer-reviewed
    Aim To highlight the significant conservation challenge of evaluating peripheral endemic vertebrates in island archipelago systems and to assess empirically the complexities of approaches to conservation genetic studies across political and biogeographic boundaries. To demonstrate the poignant need for international collaboration and coordination when species delimitation problems with high conservation concern involve island endemics with biogeographically peripheral ranges. Location Southeast Asia, Lanyu Island, Taiwan, and the Philippines. Methods Genetic samples were collected and sequenced for one mitochondrial gene and five nuclear loci for species of the Gekko mindorensis-G. kikuchii species complex in Southeast Asia. We used maximum likelihood and Bayesian phylogenetic methods and coalescent-based species delimitation analyses to estimate phylogeographic relationships, construct multilocus haplotype networks and test putative species boundaries. Results Phylogenetic and population genetic analyses suggest that Kikuchi's Gecko may represent a peripheral population of a widespread species distributed from the northern Philippines to Taiwan. However, we identify a discrepancy between inferences of species boundaries resulting from methods based on allele frequencies versus coalescent-based methods that incorporate evolutionary history. Coalescent-based analyses suggest that G. kikuchii may be a distinct evolutionary lineage. Our study underscores the need for coalescent-based methods in conjunction with population genetic approaches for conservation genetic assessments of widespread species. Main conclusions This study joins a few recent works suggesting that Philippine-derived anomalies in the fauna of Lanyu (and possibly greater Taiwan) are worthy of careful reconsideration. Determining whether each is the result of recent human-mediated introduction or (possibly more ancient) natural dispersal should be the goal of future studies on this seldom-conceived biogeographic relationship. Isolated species endemic to islands on the outer periphery of biogeographic and political regions represent particular conservation challenges. This is especially true if a species occurs on an isolated island that is allied biogeographically with one nation, but politically administered by another.
  • Fujii, R, Ota, H, Toda, M
    Chelonian Conservation and Biology, 13(2) 191-201, Jun, 2014  Peer-reviewed
  • Masanao Honda, Takaki Kurita, Mamoru Toda, Hidetoshi Ota
    ZOOLOGICAL SCIENCE, 31(5) 309-320, May, 2014  Peer-reviewedLast author
    The Kuroiwa's eyelid gecko Goniurosaurus kuroiwae is an endangered species in a state of relict endemism in the Central Ryukyus, Japan, and is divided into five subspecies. We analyzed variations in sequence data for approximately 1900 base positions of mitochondrial 12S and 16S rRNA, and cytochrome b genes from samples representing all recognized subspecies of G. kuroiwae together with those from congeneric species in order to test the relevant previous phylogenetic hypotheses and discuss biogeographical implications in the degree and pattern of genetic divergence within G. kuroiwae. Our results, while confirming a previous molecular phylogenetic hypothesis proposed on the basis of much smaller data set, negate the relationships hypothesized on morphological grounds by explicitly supporting: 1) the primary dichotomy, with substantial genetic divergence, between G. k. splendens from the Amami Island Group and the remaining subspecies all from the Okinawa Island Group; and 2) the presence of at least six independent lineages within the latter, indicating non-monophyly for two of the subspecies, G. k. kuroiwae and G. k. orientalis, in the current taxonomic definitions. The marked genetic divergence between populations of the two island groups seems to have initiated in the middle Miocene, i.e., prior to formation of straits that have consistently been separating these two island groups since the early Pleistocene. All populations of G. kuroiwae are regarded as endangered from the viewpoint of conservation genetics.
  • Yuki Koizumi, Hidetoshi Ota, Tsutomu Hikida
    ZOOLOGICAL SCIENCE, 31(4) 228-236, Apr, 2014  Peer-reviewed
    Scincella boettgeri and S. formosensis are respectively small-bodied, morphologically similar skinks, endemic to the Southern Ryukyus and Taiwan. To estimate the phylogeography of both species, we performed phylogenetic analyses using the mitochondrial cytochrome b (cyt b) gene sequences based on 102 individuals of S. boettgeri from 12 Southern-Ryukyu islands and 33 S. formosensis from six localities in Taiwan. A total of 67 haplotypes were recognized for S. boettgeri and 21 for S. formosensis. The phylogenetic analyses revealed that the populations of Scincella spp. in the Southern Ryukyus and Taiwan are composed of three major clades, the Yonagunijima clade from Yonagunijima Island, the Southern-Ryukyu clade from the Southern Ryukyus exclusive of Yonagunijima Island, and the Taiwan clade from Taiwan. These clades showed high levels of genetic divergence, suggesting that the species have been isolated since the Early Pliocene. The Southern-Ryukyu and Taiwan clades were further divided into three and four subclades, respectively. Two of the three Southern-Ryukyu subclades are partially sympatric on two islets of the Yaeyama Group, suggesting this population represents a secondary contact subsequent to their allopatric differentiations.

Misc.

 154

Books and Other Publications

 60

Presentations

 63

Teaching Experience

 16

Professional Memberships

 18

Research Projects

 40

Academic Activities

 69

Social Activities

 67

Media Coverage

 70