著者
Shintaro TANABE Eiiti KASUYA Takahisa MIYATAKE
出版者
The Herpetological Society of Japan
雑誌
Current Herpetology (ISSN:13455834)
巻号頁・発行日
vol.38, no.1, pp.14-22, 2019 (Released:2019-02-28)
参考文献数
29

The traits of many animal species exhibit individual and sexual differences. Individuals repeatedly receiving a stimulus without harm become habituated to it. However, few studies have been conducted on individual and sexual differences in the process of habituation to unfamiliar food stimuli. Therefore, we hypothesized that individual differences or sexual differences would be observed in reaction to an in-lab food-stimuli presentation of potential prey items (after that “food stimuli”). We tested the hypothesis using the Japanese tree frog Hyla japonica, and conducted statistical analyses of these results. A generalized linear model (GLM) showed individual and sexual differences in time to get used to the food stimuli. Females habituated more rapidly to food stimuli than males. The difference between sexes is discussed in view of two ultimate and one proximate reasons.
著者
Masafumi MATSUI Yasuchika MISAWA Kanto NISHIKAWA Tomohiko SHIMADA
出版者
日本爬虫両棲類学会
雑誌
Current Herpetology (ISSN:13455834)
巻号頁・発行日
vol.36, no.2, pp.116-126, 2017 (Released:2017-08-25)
参考文献数
27

A new species of salamander, Hynobius mikawaensis, is described from the eastern part of Aichi Prefecture, central Japan. It is a lentic breeder of the so-called H. lichenatus species group, and is phylogenetically closest to H. nigrescens and H. takedai. Morphologically, it differs greatly from H. nigrescens, but is very similar to H. takedai, from which it could be differentiated by some morphological traits such as shorter forelimbs and hindlimbs, but longer axilla-groin length, all relative to snout-vent length. The new species from the southern Pacific side of central Japan is completely separated geographically from H. nigrescens and H. takedai, both from the northern, Japan Sea side, by the intervening high mountains. This north/south disjunctive distributional pattern is highly unique among Japanese fauna. The range of the species is so small that immediate measure of conservation is necessary.
著者
Masafumi MATSUI Hiroshi OKAWA Kanto NISHIKAWA Gen AOKI Koshiro ETO Natsuhiko YOSHIKAWA Shingo TANABE Yasuchika MISAWA Atsushi TOMINAGA
出版者
The Herpetological Society of Japan
雑誌
Current Herpetology (ISSN:13455834)
巻号頁・発行日
vol.38, no.1, pp.32-90, 2019 (Released:2019-02-28)
参考文献数
81

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 from complete sequences of the mitochondrial cytochrome b gene, and nuclear genome differentiations were estimated by multiplexed inter simple sequence repeat genotyping by sequencing (MIG-seq). The results suggest that H. nebulosus hitherto recognized consists of at least nine species. We applied existing names to two of them, H. nebulosus (Temminck et Schlegel) and H. vandenburghi Dunn, and described seven others as new species.
著者
KOJI TANAKA AKIRA MORI
出版者
The Herpetological Society of Japan
雑誌
Current Herpetology (ISSN:13455834)
巻号頁・発行日
vol.19, no.2, pp.97-111, 2000 (Released:2009-03-27)
参考文献数
234
被引用文献数
7

Characteristic defensive behaviors of snakes and their ecological and morphological correlates have been well documented. Biological interpretations of these characteristics, however, often suffer from a paucity of information on actual predators of snakes. Concerning natural predators of Japanese snakes, neither quantitative data nor a systematic review are available. Here, we review and synthesize the published accounts of predators of snakes in Japan. We confirmed 59 species/subspecies of predators and 21 species of prey snakes. We hope that this review will stimulate biologists and naturalists to record further predatory events on snakes and help clarify the defensive mechanisms of snakes.
著者
MORIYA FUKASHI MORIYA KATORI
出版者
The Herpetological Society of Japan
雑誌
Current Herpetology (ISSN:13455834)
巻号頁・発行日
vol.30, no.2, pp.173-176, 2011

The seacoast of Isumi City, Chiba Prefecture, Japan, is one of the northernmost nesting sites of loggerhead sea turtle <i>Carettta caretta</i> in the North Pacific. We observed nesting and hatching events of this species and investigated for asynchronous emergence of hatchlings from 2008 to 2010. In 2008, hatchlings emerged from all nests from July to September, but in 2009 and 2010, most clutches laid in August failed to hatch probably due to low ambient temperature resulting from low atmospheric temperature with insufficient sunshine. In one nest constructed in early July of 2010, hatchling emergence started in early September and completed in late September, 18 days after initial emergence. This extends the previous maximum records of duration of emergence from a single nest by 13 days.<br>
著者
LOVICH JEFFREY E. PUFFER SHELLIE R. AGHA MICKEY ENNEN JOSHUA R. MEYER-WILKINS KATHIE TENNANT LAURA A. SMITH AMANDA L. ARUNDEL TERENCE R. BRUNDIGE KATHLEEN D. VAMSTAD MICHAEL S.
出版者
日本爬虫両棲類学会
雑誌
Current herpetology (ISSN:13455834)
巻号頁・発行日
vol.37, no.1, pp.40-57, 2018
被引用文献数
1

<p>Agassiz's desert tortoise (<i>Gopherus agassizii</i>) reaches the southern edge of its range in the Sonoran Desert of California. The reproductive ecology of this wide-ranging species is understudied here compared to populations in the adjacent Mojave Desert. Understanding potential geographic variation in reproductive ecology is important for effective management of conservation-reliant species like <i>G. agassizii</i>. We studied the fecundity and clutch phenology of female <i>G. agassizii</i> at two study sites in the Sonoran Desert region of Joshua Tree National Park over five years (1997–1999–2015–2016) spanning two of the strongest El Niño events on record and an epic drought. Across all years, mean clutch size was 4.3±1.5 eggs, mean clutch frequency was 1.78 clutches/female/year, and mean X-ray egg width was 36.51±1.56 mm, all of which are comparable to other published studies both in the Sonoran and Mojave deserts of California. Our results generally support earlier published findings that <i>G. agassizii</i> utilize a bet-hedging strategy of consistently producing small clutches almost every year, even during times of low annual primary productivity. A regionally warmer climate in the Sonoran Desert of California appears to have an effect on the timing of egg production, as the earliest dates of egg visibility in our study (April 6) were approximately two weeks earlier than the earliest dates reported for <i>G. agassizii</i> in the Mojave Desert. Shelled eggs were no longer visible in tortoises after mid-June in all years but the El Niño year 1998, when eggs were visible until mid-July.</p>
著者
Natsuhiko YOSHIKAWA
出版者
日本爬虫両棲類学会
雑誌
Current Herpetology (ISSN:13455834)
巻号頁・発行日
vol.35, no.1, pp.69-72, 2016 (Released:2016-02-26)
参考文献数
8

Antipredator behavior of Cynops pyrrhogaster was observed in the field. A male, found in a temporal pool (11.7C), tightly coiled his body around the observer’s finger (putative model of predator) when he was touched from lateral side. The body-coiling was formed both dextrally and sinistrally, depending on direction from which the newt’s body was touched. Undulation of tail and noxious secretion accompanied the behavior. The coiling-around behavior was aborted immediately when the newt lost physical contact with finger. Apart from this, pushing on the head with a finger caused Unken reflex, which is commonly known as defensive behavior of newts. It is suggested that C. pyrrhogaster varies their defensive behavior depending on the situation of encounter with the predator.
著者
Makoto M. ITOH
出版者
The Herpetological Society of Japan
雑誌
Current Herpetology (ISSN:13455834)
巻号頁・発行日
vol.36, no.2, pp.135-141, 2017 (Released:2017-08-25)
参考文献数
16

In most frogs, males emit calls in the reproductive seasons, whereas females usually do not emit calls. Females of only several frog species have been known to vocalize. I here report female vocalization in two ranid species, Pelophylax nigromaculatus and P. porosus brevipodus in their overlapping reproductive season. Females of these species called in both intraspecific and interspecific interactions. There were no clear differences in acoustic characteristics of female calls between the two species or between interspecific and intraspecific interactions. Based on the situations in which females called, it is implied that functions of the female calls of P. nigromaculatus and P. p. brevipodus are quite different from those of female calls in frogs hitherto reported.
著者
Dzung Trung LE Tao Thien NGUYEN Kanto NISHIKAWA Son Lan Hung NGUYEN Anh Van PHAM Masafumi MATSUI Marta BERNARDES Truong Quang NGUYEN
出版者
日本爬虫両棲類学会
雑誌
Current Herpetology (ISSN:13455834)
巻号頁・発行日
vol.34, no.1, pp.38-50, 2015 (Released:2015-02-27)
参考文献数
23
被引用文献数
4

We describe a new species of Tylototriton from northwestern Vietnam and northern Thailand based on morphological and molecular evidence. Tylototriton anguliceps sp. nov. is distinguishable from all the other congeners by the bright to dark orange markings on the head, body, and tail, prominent dorsal and dorsolateral ridges (crests) on the head, skeletal connection between maxillary and pterygoid, and unique mitochondrial and nuclear DNA sequences. Our molecular data show that the new species is nested within the clade comprising T. uyenoi, T. shanjing, T. verrucosus, and T. yangi. The new species is expected to be recorded from other countries in the Indochina region such as southern China, western Myanmar and northern Laos in the future.
著者
Kanto NISHIKAWA Ding-Qi RAO Masafumi MATSUI Koshiro ETO
出版者
日本爬虫両棲類学会
雑誌
Current Herpetology (ISSN:13455834)
巻号頁・発行日
vol.34, no.1, pp.67-74, 2015 (Released:2015-02-27)
参考文献数
24
被引用文献数
2

We assessed taxonomic relationship of Tylototriton daweishanensis Zhao, Rao, Liu, Li and Yuan, 2012 and T. yangi Hou, Li and Lu, 2012 using mitochondrial DNA sequence data and found them to be as closely related as to be regarded as conspecific. This result, together with available morphological information, strongly indicates that T. daweishanensis is a junior synonym of T. yangi.
著者
OKAMOTO KEI KAMEZAKI Naoki
出版者
The Herpetological Society of Japan
雑誌
Current Herpetology (ISSN:13455834)
巻号頁・発行日
vol.33, no.1, pp.46-56, 2014
被引用文献数
4 1

Morphological variations were analyzed for green turtles, <i>Chelonia mydas</i>, on the basis of 127 individuals captured in the coastal waters of Japan. They were explicitly divided into two groups by plastral coloration—the yellow type and the black type. To statistically assess the morphometric differences between these color types, analysis of covariance was performed for each of 28 external measurements using the standard straight-line carapace length (SCL) as the covariate. Results indicated that the yellow and black types significantly differ in ratios to SCL of distances from the nuchal notch to the outermost point of boundry between the 11th and the preceding (10th) marginals, and also to the boundary of the 11th marginal, last (fifth) vertebral, and last (fourth) pleural on both sides. Such morphometric covariations with plastral coloration in <i>C. mydas</i> sensu lato, as well as sympatric occurrences of the two color types in the Japanese waters, collectively support the validity of the black type as a distinct species, <i>Chelonia agassizii</i>.
著者
Natsuhiko YOSHIKAWA Masafumi MATSUI
出版者
日本爬虫両棲類学会
雑誌
Current Herpetology (ISSN:13455834)
巻号頁・発行日
vol.32, no.1, pp.9-25, 2013 (Released:2013-02-22)
参考文献数
25
被引用文献数
2

Recent phylogenetic studies using mtDNA and allozymes have revealed the presence of large genetic differentiation within a Japanese clawed salamander, Onychodactylus japonicus, suggesting the presence of several cryptic taxa in this species. Based on morphological analyses, we describe one of them from the Tsukuba Mountains of Ibaraki Prefecture, in the Kanto district of eastern Honshu, as a new species, Onychodactylus tsukubaensis. It is a member of the japonicus species complex of Onychodactylus, and differs from the other species of the complex by a relatively short tail, wide head, and large number of vomerine teeth.
著者
HIROYUKI SATO HIDETOSHI OTA
出版者
日本爬虫両棲類学会
雑誌
Current Herpetology (ISSN:13455834)
巻号頁・発行日
vol.20, no.1, pp.19-25, 2001 (Released:2009-03-27)
参考文献数
16
被引用文献数
6

The male and female karyotypes were examined for 10 specimens of the Chinese soft-shelled turtle, Pelodiscus sinensis, from the main islands of Japan and Taiwan by the bone marrow air-dry technique. One specimen of Dogania subplana was also examined karyologically. Although both P. sinensis and D. subplana had 2n=66 chromosomes, they showed an interspecific variation in chromosome morphology. No karyotypical differences were evident between the Japanese and Taiwanese samples of P. sinensis, or within either of them. Comparisons of the present results with previously reported trionychine karyotypes indicate that there are some interspecific and intraspecific variations in centromeric positions of several macrochromosome pairs in this subfamily.