Atsushi Tominaga

University of the Ryukyus · Faculty of Education

Sperm motility‐initiating substance (SMIS) is an oviductal protein critical for internal fertilization in urodeles. It contributes to the establishment of various reproductive modes in amphibians and is thus a unique research model for the gene evolution that gamete‐recognizing ligands has been diversified among animal species. In this study, a par...

The Anderson's crocodile newt, Echinotriton andersoni, is an endangered species distributed in the islands of Central Ryukyus, Japan. This species is well known to show high intraspecific genetic variation among islands, but its morphological variation has not been explored. We examined the skull variation in this species including enigmatic specim...

A crocodile newt, Echinotriton raffaellii, recently described from the Amami islands in the Ryukyu archipelago, western Japan has been regarded as Amami lineage of E. andersoni from the Okinawa islands, to which it is morphologically very similar, but genetically divergent. In the original description of E. raffaellii, only two specimens, including...

Discrepancies in geographic variation patterns between nuclear DNA and mitochondrial DNA (mtDNA) are the result of the complicated differentiation processes in organisms and are the key to understanding their true evolutionary processes. The genetic differentiation of the northern and Southern-Izu lineages of the Japanese newt, Cynops pyrrhogaster,...

The family Rhacophoridae, including Buergeria japonica, shows a great diversity of reproductive patterns, but the knowledge of developmental processes is still limited. The genus Buergeria is a sister group to all other rhacophorids and shows a conservative, probably primitive, reproductive mode for this family. Thus, it is valuable to clarify the...

While research on frog chytrid fungus Batrachochytrium dendrobatidis (Bd), an infectious disease that threatens amphibian diversity, continues to advance worldwide, little progress has been made in Japan since around 2010. The reason for this is, which we pointed out in 2009, that the origin of frog chytrid fungus may be in the East Asian region, i...

Low osmolality of freshwater and/or sperm motility-initiating substance (SMIS) induce amphibian sperm motility through increases in intracellular Ca2+. In the internally fertilizing newt Cynops pyrrhogaster, the sperm motility-initiating substance engages T type voltage-dependent Ca2 + channels and N-methyl D-aspartate-type glutamate receptors to i...

The maintenance mechanisms of hybrid zones between two lineages/species and their gene flow dynamics are major topics for speciation studies. Elucidating these dynamics can help us to understand the process of speciation. The newt Cynops pyrrhogaster is distributed on the main islands of Japan and comprises five mitochondrial DNA (mtDNA) lineages....

The diet of the nonnative American Bullfrog Lithobates catesbeianus occurring in Ogimi Village of Okinawajima, Ryukyu Archipelago, is investigated. Seventy two of 89 frogs (nine adults, five subadults, and 58 juveniles) captured had food items in its stomach. We identified a total of 64 taxa from 253 food items. Our analyses show that (1) the diet...

A Japanese microhylid, Microhyla okinavensis, originally described from Okinawajima Island, middle Ryukyus, was long synonymized with M. ornata from India. However, molecular phylogenetic studies revealed its distinct species status from M. ornata, and more recent phylogenetic study revealed the population from the Yaeyama Group of the southern Ryu...

Buergeria japonica, long thought to be a single species widely occurring on the Ryukyu Archipelago and Taiwan, proved to include three genetically differentiated clades, (1) the Northern and Central Ryukyu, (2) the Southern Ryukyu and Northern Taiwan, and (3) the Southern Taiwan clades. The Southern Taiwan clade has already been split from the othe...

The endangered crocodile newt, Echinotriton andersoni, is a relatively large species of the family Salamandridae and is distributed on six islands in the central part of the Ryukyu Archipelago, Japan. Because of an originally small distribution range and recent habitat loss, this species has been steadily declining in number. To elucidate fine-scal...

A lotic-breeding salamander Hynobius stejnegeri, formerly called H. yatsui, from western Japan is revised based on genetic and morphological evidence, and three species are described: H. guttatus sp. nov. from Chubu-Kinki districts of Honshu Island, H. tsurugiensis sp. nov. from east highland of Shikoku Island, and H. kuishiensis sp. nov. from othe...

We sequenced mitochondrial cytochrome b gene of 14 samples of Siberian salamander, Salamandrella keyserlingii, from a population newly found in Kamishihoro-cho, eastern Hokkaido, Japan, and conducted phylogenetic analysis to reveal genetic identity of the population. The Kamishihoro population was most closely related to the geographically adjacent...

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 ar...

The abundant clouded salamander from western Japan, Hynobius nebulosus, has long been considered a single widespread species, although some authors have suggested the inclusion of several cryptic species. This led to a molecular and morphological analysis of populations from all parts of the known range. Phylogenetic relationships were inferred fro...

Two new species of lotic-breeding salamanders, Hynobius sematonotos and H. oyamai, are described from Chugoku district and northeastern Kyushu district, respectively, western Japan. They are members of the so-called H. naevius group and are phylogenetically close to H. naevius, H. katoi, and H. hirosei but divergent from them with large genetic dis...

Hybridizations on a secondary contact zone between 2 diverged lineages can have various evolutionary consequences, including the genetic replacement of one lineage by another. We detected such a case between 2 lineages (the Central and Western lineages) of the Japanese fire-bellied newt, Cynops pyrrhogaster in the Chugoku district of western Japan....

The Japanese giant salamander, Andrias japonicus, is known to exhibit very low genetic diversity, but the number of individuals surveyed in a population is limited by now. We investigated partial sequences (673 bp) of mitochondrial cytochrome b gene in 180 specimens of a population from the Inuyama Head Works on the Kiso River, Central Japan, over...

Examination of the holotype of Hynobius stejnegeri Dunn, 1923 revealed that the species is identical with H. yatsui Oyama, 1947, recently resurrected from H. naevius (Temminck and Schlegel, 1838). The name H. yatsui is therefore relegated to a subjective junior synonym of H. stejnegeri. The latter name, however, has been widely applied to an amber-...

Chinese populations of the endangered Siberian salamander Ranodon sibiricus are reported to have diverged only about 120 years ago, and to have the lowest genetic diversity of any amphibian. However, these conclusions require verification, as the main range of the species is in Kazakhstan. Moreover, the generation time used for estimating divergenc...

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009;...

This plot is not part of the published stance but derives from it. The plot shows the number of authors by geographic region (courtesy of Dr. Diego Astua).

Using mitochondrial DNA sequences, we surveyed genetic features of 12 individuals of Cynops pyrrhogaster introduced into Hachijojima Island, in order to estimate their possible origin in the main islands of Japan. The phylogenetic analysis revealed that the 12 examined newts of the introduced population display no genetic diversity and share charac...

Batrachochytrium dendrobatidis (Bd) infects Anuran larvae (tadpole) mouthparts and causes oral chytridiomycosis, which can be diagnosed in tadpoles by detecting mouthparts deformities. However, oral chytridiomycosis may or may not be observable, depending on species, tadpole stage and season, and has never been reported in Japan. We aimed to observ...

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. Buer...

Batrachochytrium dendrobatidis (Bd) is the pathogen responsible for chytridiomycosis, a disease that is associated with a worldwide amphibian population decline. In this study, we predicted the potential distribution of Bd in East and Southeast Asia based on limited occurrence data. Our goal was to design an effective survey area where efforts to d...

We investigated phylogenetic positions of Cynops pyrrhogaster from nine localities in the central and southern parts of the Izu Peninsula using the mitochondrial cyt b gene. We revealed that the central and the southern populations are phylogenetically remote. The central Izu lineage belongs to the CENTRAL clade occurring from Chubu through Kinki t...

The Japanese fire-bellied newt Cynops pyrrhogaster, endemic to mainland Japan is ranked as Near Threatened in the red list of Japan. However, microsatellite markers effective for estimating genetic diversity and structures for its conservation measures have never been reported. Therefore, we developed fifteen novel microsatellite markers for this s...

The Japanese fire-bellied newt Cynops pyrr-hogaster, endemic to mainland Japan is ranked as Near Threatened in the red list of Japan. However, microsatellite markers effective for estimating genetic diversity and structures for its conservation measures have never been reported. Therefore, we developed fifteen novel microsat-ellite markers for this...

The international trade in amphibians is believed to have increased the spread of Batrachochytrium dendrobatidis (Bd), the fungal pathogen responsible for chytridiomycosis, which has caused a rapid decline in amphibian populations worldwide. We surveyed amphibians imported into Japan and those held in captivity for a long period or bred in Japan to...

We surveyed the genetic diversity and genetic differentiation of an endangered frog, Babina holsti, endemic to Okinawajima and Tokashikijima Islands of the Ryukyus, to elucidate its divergence history and obtain basic data for its conservation. Genetic differentiation between the two island lineages is moderate (3.1% p-distance in the cyt b gene)....

To determine whether the chytrid fungus Batrachochytrium dendrobatidis (Bd) found on the hellbender Cryptobranchus alleganiensis in the southern US is endemic or exotic, we identified the genetic type of this fungus using partial DNA sequences of the internal transcribed spacer (ITS) region. We identified 3 genetic types, which are found on Japanes...

Population structure analyses in an endangered salamander, Echinotriton andersoni (Caudata: Salamandridae), elucidated by microsatellite markers Anderson's crocodile newt (Echinotriton andersoni) is a relatively large newt belonging to the family Salamandridae and is endemically distributed on 6 small islands in Southwestern Japan. Unfortunately th...

We investigated the phylogenetic relationships and estimated the historical demography of the Japanese fire-bellied newt, Cynops pyrrhogaster, from Japanese mainlands using 1407-bp sequences of the mitochondrial DNA (NADH6, tRNAglu, cyt b) and 1208-bp sequences of nuclear DNA (Rag-1) genes. Phylogenetic trees based on mitochondrial DNA revealed fou...

The Anderson's crocodile newt, Echinotriton andersoni, is considered a relic and endangered species distributed in the Central Ryukyus. To elucidate phylogenetic relationships and detailed genetic structures among populations, we analyzed variation in the mitochondrial cytochrome b gene. Results strongly support a primary dichotomy between populati...

We investigated the phylogenetic relationships and estimated the history of species diversification and character evolution in two ichthyophiid genera: Caudacaecilia and Ichthyophis. We estimated the phylogenetic relationships of 67 samples from 33 localities in Southeast Asia from 3840-bp sequences of the mitochondrial 12S rRNA, 16S rRNA, and cyt...

カワヒバリガイは，中国，朝鮮半島原産の淡水二枚貝で，日本，台湾，南米各国に 侵入し，大規模な付着被害を起こしている。本研究では日本の個体群の遺伝的組成を 調査することで，その起源や侵入経路の推定を試みた。その結果，日本の個体群は東 日本グループと西日本グループの2 群に分けられ，海外から少なくとも2 回侵入した ことが明らかになった。遺伝的組成の比較から東日本グループの起源は上海，韓国で あることが推定された一方で，西日本グループの起源は特定できなかった。西日本グ ループは近畿から関東北西部に分布し，水系間に遺伝的組成の大きな違いが見られな いことから，国内で飛び火的な移動に伴う分布拡大が起きていると考えられた。また， 同水系内の個体群間でも遺伝的組成は類似しており，河川や水利施設を介した水...

We performed this study in order to establish an effective, simple and safe treatment for chytridiomycosis. The subjects were 12 amphibians (11 anurans of 4 different species and 1 urodela) diagnosed with chytridiomycosis by clinical signs and a PCR test. A 0.01% aqueous solution of the antifungal agent itraconazole was used to treat the subjects,...

Based on morphological and molecular analyses, Xiong et al. (2007) synonymized Hynobius yunanicus Chen et al. with Pachyhynobius shangchengensis Fei et al., both from continental China. Their study, however, was not substantial enough in that morphology of types of neither species was compared, only a partial mitochondrial cytochrome b (cyt b) sequ...

We investigated the phylogenetic relationships and phylogeography among individuals of the endemic newt (Cynops ensicauda) of the Central Ryukyus, Japan based on the mitochondrial cytochrome b gene. The results of phylogenetic analyses showed the presence of remarkable differentiation between assemblages from the Amami and Okinawa Island Groups, su...

Limnoperna fortunei (golden mussel) is an aggressive freshwater invasive species naturally distributed in China, Korea, and South eastern Asian countries. This species was introduced into East Asian and South American countries from 1965 to the 1990s. In Japan, the golden mussel was first found in Lake Biwa in 1992 and it is known to be distributed...

We investigated the phylogenetic relationships and estimated the history of species diversification and biogeography in the bufonid genus Ansonia from Southeast Asia, a unique organism with tadpoles adapted to life in strong currents chiefly in montane regions and also in lowland rainforests. We estimated phylogenetic relationships among 32 named a...

The salamander Hynobius yatsui from southwestern Japan was formerly regarded as a small-sized group of H. naevius, but has recently been resurrected as a distinct species. We investigated the phylogeography of H. yatsui from Kyushu Island using partial sequences of the mitochondrial cytochrome b gene. We detected 49 haplotypes in 181 individuals fr...

The phylogenetic relationships among 46 samples from 27 populations of the Japanese giant salamander, Andriasjaponicus and its congener, A. davidianus from China was investigated, using 3664 bp sequences of the mitochondrial genes NADH1, NADH3, cyt b and CR, partial NADH6 and intervening genes. In phylogenetic trees constructed by MP, ML, and Bayes...

We conducted molecular phylogenetic analyses to confirm taxonomic relationships and to delimit distributional ranges of Siberian salamanders, Salamandrella keyserlingii and Salamandrella schrenckii, and to elucidate the origin of the isolated population of this species complex on Hokkaido, Japan. Phylogenetic trees constructed by MP, NJ, ML, and Ba...

A Japanese small salamander, Hynobius naevius (Temminck and Schlegel, 1838), has recently proven to include two species (larger [A] and smaller [B]) that are reproductively isolated and are genetically and morphologically distinct from each other. Of these two species, Species A is considered to correspond to true H. naevius. To determine the name...

A small Japanese salamander, Hynobius naevius, long considered a single species, has recently proven to include two groups (Group A=large type and Group B=small type) that are split at the species level. We compared the type series of H. naevius with specimens of the two groups to clarify which of them corresponds to true H. naevius, and to estimat...

Using complete sequences of cytochrome b (cyt b) and control region (CR; D-loop) genes of mitochondrial DNA, we investigated the phylogenetic relationships and phylogeography among populations of the salamander Hynobius tokyoensis in northern Japan. Inclusion of populations from Aichi, Chubu region within Hynobius nebulosus by previous results was...

Japanese giant salamander, Andrias japonicus inhabits in the Maefukase and Kawakami Rivers of the Maefukase River system in Iga City, Mie Prefecture, where construction of a dam is planned. Disjunction of local populations and subsequent reduction of each population within the river system may induce loss of genetic diversity and ultimate extinctio...

Using mitochondrial 12S and 16S rRNA sequences, we investigated phylogenetic relationships among populations of the endemic Japanese salamander Hynobius naevius. Monophyly of this species was recovered only in the maximum parsimony tree and was unresolved in maximum likelihood and Bayesian trees. Instead the following four haplotype clades consiste...

Hynobius naevius, distributed on western Honshu, Shikoku, and Kyushu Islands of Japan, includes two genetically distinct groups (Groups A and B) that have never been delimited morphologically. Using specimens from the entire species range, we investigated the possibility of distinguishing these groups morphologically. Multivariate analyses of morph...

A survey of genetic variation of lotic breeding salamander Hynobius naevius by starch gel electrophoresis using 26 populations from southwestern Japan revealed the presence of two genetically distinct groups (GROUP-A and B) which overlap distributional ranges in some parts of Kyushu. Degree of genetic differentiation between the two groups was larg...

A survey to examine genetic variation among Hynobius naevius from four localities of Fukuoka Pref., northern Kyushu, Japan, resulted in the detection of two, sympatric, genetic types (A and B) that are clearly different in the allelic frequencies of four loci (ACOH-A, ACOH-B, ADH-A, and SOD-A) in each locality. Morphological investigations between...