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Context The common methods for detecting prey in faeces are traditional morphological examination of digested prey remains and faecal DNA (fDNA) metabarcoding. Although recent studies have shown that fDNA metabarcoding can identify prey that is excreted without morphologically identifiable remains, it is unclear whether fDNA metabarcoding provides a more comprehensive assessment of diet than morphological analyses. Aims We aimed to compare prey detection abilities of morphological and fDNA-metabarcoding assays by evaluating similarities and differences of estimated prey communities. We also aimed to provide the first comprehensive prey composition of an endangered ground-dwelling gecko, Goniurosaurus kuroiwae, which will contribute to the conservation management of this species. Methods We identified the prey consumed by G. kuroiwae by morphological examination and fDNA metabarcoding using the same series of faecal samples. For these two methods, we compared the overall community composition of prey items and the detection rate for each prey type. We also tested for environmental and ontogenetic variation of the composition of prey items consumed. Key results When comparing the two methods there were significant differences in the composition of prey communities that were identified from the same series of faecal samples. The fDNA metabarcoding analyses showed the higher rate of detection of earthworms, amphipods and coleopteran and lepidopteran larvae, which lack hard exoskeleton or have small body sizes. The morphological assay allowed identification of a few prey types, including spiders and earwigs, more frequently than fDNA metabarcoding. Combined use of both methods revealed that G. kuroiwae consumed large-sized invertebrates with a slight ontogenetic shift from small-sized invertebrates to large-sized ones. Conclusions Although fDNA metabarcoding showed the higher overall prey detection rate, it did not include all the prey items detected by morphological analysis. The complementary use of both methods can yield better understanding of the prey composition of invertebrate-consuming animals represented by reptiles and amphibians. Implications We have shown that the most comprehensive reconstruction of prey composition from faeces will be achieved by combining results from both fDNA metabarcoding and morphological analyses.

Viviparous reproduction has evolved independently more than 100 times in the evolutionary history of Squamata (lizards and snakes). Adaptation to cold climates is the dominant hypothesis explaining...

The jaws of vertebrates display a striking diversity in form and function, but they typically open and close like a trapdoor rather than sliding like a saw. Here, we report unique feeding behaviour in the blunt-headed snail-eating snake, Aplopeltura boa (family Pareidae), where the snake cuts off and circumvents the indigestible part (the operculum) of its prey in the mouth using long sliding excursions of one side of the mandible, while the upper jaws and the mandible on the other side maintain a stable grasp on the prey. This behaviour, which we call ‘mandibular sawing’, is made possible by extraordinarily independent movements of the jaw elements and is a surprising departure from usual feeding behaviour in vertebrates., ヘビが顎をノコギリのように使うことを発見 --ボルネオ島での爬虫両生類の生態調査で--. 京都大学プレスリリース. 2020-07-31.

Gunung Mulu National Park (GMNP) in northwestern Borneo is marked by high species diversity and diverse environments. We present one new amphibian and ten new reptile records from GMNP and its surrounding area. In the records, Asthenodipsas jamilinaisi and Garthius chaseni were newly recorded in the Sarawak State. We also present the first record of Cyrtodactylus muluensis from outside of GMNP and the second record of Opisthotropis typica from the park. Combined with previous information, a total of 108 amphibians and 104 reptiles are known from GMNP, and their preferred habitat types are diverse. Furthermore, observed male-male combat of Dopasia buettikoferi is the first detailed description of the genus. Two color morphs of D. buettikoferi had an identical ND2 haplotype and appeared to be the same species. The present study provides new information about Bornean amphibians and reptiles, and also emphasizes the importance of continuous monitoring.

Short Communications

A new species of Asian rock gecko, genus Cnemaspis , is described from Padawan, western Sarawak, Malaysian Borneo. The new species forms a clade with C . paripari and C . nigridia of the C . nigridia group in a mitochondrial DNA phylogeny and is similar to them morphologically in some characters such as caudal scalation. It differs from the other Asian Cnemaspis species in its unique combination of snout–vent length (up to 62.7 mm), 4–9 precloacal pores in males, keeled subcaudals with an enlarged, smooth, median row, presence of ventrolateral caudal tubercles, and coloration (head and upper flanks dark-yellow; anterior portion of tail black; posterior portion of tail white with black, paravertebral blob). Phylogenetic relationships within the C. nigridia group and the distributional ranges of species within the group suggest allopatric speciation by geographic isolation.

Eight microsatellite markers for the population genetics and evolutionary ecology of Ischnura senegalensis (Rambur 1842), which shows body color polymorphism in females, were developed using a streptavidin-bead enrichment library and pyrosequence by a next generation sequencer. The number of alleles per locus and effective number of alleles ranged from 3 to 11 and from 1.24 to 5.51, respectively. Observed and expected heterozygosities were 0.18–0.75 and 0.19–0.77, respectively. No linkage disequilibrium between loci was detected. One locus, IsenAC75, deviated significantly from the Hardy–Weinberg equilibrium, and the locus and additional two loci, IsenAC40 and IsenAC8, were suspected for the presence of null alleles. Altogether, these eight microsatellite loci are considered to be useful for population genetic analyses because of the high polymorphic status and independency.

Hemidactylus flaviviridis was found at the Narita International Airport in a cargo that arrived from Shanghai, China. The specimen was identified using morphological and molecular techniques. The species is distributed from the Indian subcontinent to northeast Africa and has not been previously reported from Shanghai or from other parts of eastern China. Comparison of the mitochondrial NADH dehydrogenase subunit 2 gene sequence of this individual with available data revealed that the sequence to be identical with that of the homologous gene of H. flaviviridis from Dubai, United Arab Emirates, but differed by 2.9–4.0% uncorrected p distance from conspecific samples obtained from India and Pakistan, suggesting indirect transportation of the gecko individual from around Dubai to Japan, via Shanghai. This finding highlights future risks of colonization of exotic geckos to the warm temperate and subtropical regions of East Asia.

I surveyed distribution and abundance of a recently established population of Hemidactylus frenatus on Amamioshima Island of the Ryukyu Archipelago, Japan. I also attempted to evaluate the risk of further range expansion of this species within the island. In the first record of H. frenatus from the island in 2000, its range was restricted to one building in the urban area of Naze. In my survey in 2012, however, the gecko was already widespread, being the most abundant gekkonid species in the area. Hemidactylus frenatus was also found in many sites of the island outside Naze, most of which were located in the eastern part of the island. Based on the species distribution model, this eastern biased range expansion seems to reflect the greater abundance of suitable habitats in the eastern part. Two of the three western sites of H. frenatus were isolated from its major, contiguous range in the central-eastern parts by areas with apparently unsuitable habitats and scattered favorable habitats occupied by other gekkonid species, suggesting that H. frenatus there had originated from individuals artificially transported within the island. The species distribution model also indicated the presence of suitable but unoccupied habitats in the southwestern part, predicting further range expansion of H. frenatus on Amamioshima in the future. My survey demonstrated the scarcity of geckos other than H. frenatus in the eastern part, probably as a result of the predominance of H. frenatus there. Based on my field observations, I also discuss the possible major carrier of H. frenatus on Amamioshima.

The eel goby, genus Taenioides (Gobiidae: Amblyopinae), inhabits muddy bottoms of estuaries or shallow areas of seas in the Indo-Pacific Ocean. Among congeners, T. cirratus ( Blyth, 1860 ) has been thought to be distributed in Japan, but taxonomic confusions remain as to which scientific names are applicable to Japanese Taenioides species, or more fundamentally, how many Taenioides species are distributed in Japan, due in part to the rarity of this group in museum collections and the morphological similarity among species. To clarify the species diversity of the genus Taenioides in Japan, we conducted phylogenetic analysis on the basis of partial mitochondrial DNA sequences and morphological observation of more than 100 specimens. As a result, four distinct species were distinguished from each other, on the basis of both genetic divergences (2.9-5.7%, 16S rRNA gene) and morphological differences (i.e., degree of development of dermal folds on the head, numbers of barbels and vertebrae). Although the identifications of four species need additional verifications, they were identified as T. anguillaris, T. snyderi, T. gracilis and T. cf. kentalleni, and the species name T. cirratus does not seem to be appropriate to any of four detected species. Museum collections indicate that the two species, which are distributed in the main islands of Japan, were collected frequently and treated as a single species. The other two were each collected only from a single locality of Okinawa Island in this study, of which one seems to be uncommon worldwide as well.

The Ryukyu ground geckos, which comprise Goniurosaurus kuroiwae (sensu stricto) and four close relatives in the Ryukyu Archipelago, face conservation threats, and are listed as endangered in the Red List of both IUCN and Japan. We developed 24 microsatellite markers in G. kuroiwae and cross-amplified for another species, G. orientalis. All 24 and 22 loci were successfully amplified and genotyped in G. kuroiwae and G. orientalis, respectively. The number of alleles per locus and expected heterozygosity at polymorphic loci ranged from 1 to 11 and 0.050–0.891, respectively, in G. kuroiwae, and ranged from 1 to 15 and 0.050–0.932, respectively, in G. orientalis.

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.