Zoological Studies最新文献

Species of the family Scorpaenidae are easily misidentified due to their similar appearances, a result of camouflaging to their surroundings. In recent years, many species from this family have been described, and generic placements of some species have been revised. Previously, there were 80 species belonging to 29 genera of the Scorpaenidae recorded in Taiwanese waters. However, their taxonomy has not been revised for decades. It is necessary to update the checklist of the Scorpaenidae occurring in Taiwanese waters based on updated morphological and molecular data. In the present study, we revised the Taiwanese scorpaenids based on 296 specimens and updated the checklist, amounting to a total of 85 species of 29 genera, of which Sebastapistes mauritiana (Cuvier) is a new record, and three species from the genera Phenacoscorpius, Scorpaenopsis, and Sebastapistes are unable to be identified to any species. Using molecular analysis, we conducted the first comprehensive DNA barcoding study of the Scorpaenidae from Taiwanese waters based on a partial cytochrome c oxidase I (COI) gene of 655 bps. A total of 118 COI sequences were generated from voucher specimens of 66 species (28 genera) identified based on morphological characters. The COI sequences of Parascorpaena maculipinnis, Scorpaena pepo, and Scorpaenopsis orientalis are new to online databases. According to the Kimura-2 Parameter (K2P) genetic distance, the mean interspecific variation (15.61%) was distinctly greater than the mean intraspecific variation (0.22%), suggesting a barcoding gap. The maximum likelihood tree showed that all lineages were supported by high bootstrap values.

Selecting ambush sites where prey abundance is high is vital for the foraging success of sit-and-wait predators. Ideal ambush sites, however, could vary due to different prey characteristics and intra-specific competition. We examined whether different life stages of a sit-and-wait predator, Trimeresurus stejnegeri, select different ambush sites, based on the observations of ambush sites of juvenile and adult snakes in three water habitats (lentic, lotic, and temporary pools) in Taiwan throughout the year. Snake stomach contents were compared between life stages in each habitat. Correlations between the monthly number of snakes observed and that of each frog species were analyzed for each habitat. Adult snakes mainly used lentic water as ambush sites and rarely used temporary pools, whereas juvenile snakes used all three habitats with a similar frequency. No clear ontogenetic diet shift was found from juveniles to adults. A high percentage of snakes from lentic water habitats had stomachs containing prey, suggesting this habitat is a better site for foraging by both juveniles and adults. Overall, our study highlights that habitat use and behavior of each prey animal and intraspecific competition as well as prey abundance should be taken into consideration when we investigate the factors that affect ambush site selection by predators.

Wing morphology, one of the most important morphological traits in bats, is closely related to their foraging habitat and strategies and has been explored as a pivotal trait for ecological and conservation studies. However, studies on wing morphology, as well as the ecology of Japanese bats, are largely lacking. In this study, we aimed to enrich the wing morphology data of Japanese bats. The wing variables, including forearm length, aspect ratio, relative wing loading, and wing tip shape index, were assessed using museum and private specimens of 34 Japanese bat species. Hierarchical clustering of the wing variables classified the bats into nine clusters to predict their foraging ecology, including the species for which ecological knowledge was lacking. Based on the ecological knowledge of Japanese bats, the aspect ratio of bats belonging to the open-space foraging guild was significantly higher than that of those belonging to other guilds. In contrast, the wing tip shape index of bats belonging to the narrow-space foraging guild was significantly higher than those belonging to the other guilds. In conclusion, our study sheds light on the complex interplay between wing morphology and foraging ecology in Japanese bats, offering insights for future research and conservation efforts.

Determining how environmental factors influence species occupancy patterns is essential to establish more efficient management strategies and policies for conserving natural populations and habitats. The Yellow-green Grosbeak (Caryothraustes canadensis) is a canopy specialist bird that occurs in the Atlantic Forest and represents a good model for evaluating how changes in regional scale characteristics can affect occupancy patterns of forest specialist species. Increasingly, occupancy models are being used to maximize these predictions because they are statistical methods that account for imperfect detection, which strengthens inferences compared to other approaches. We evaluated how multiple environmental factors affected the large-scale occupancy of C. canadensis over the last 30 years in the far north of the Brazilian Atlantic Forest, a recognized center of endemism and biodiversity. In this study, we collected secondary data from C. canadensis between 1991 and 2020. The occupancy of C. canadensis and several environmental factors that explain the historical occupancy dynamics of the species in the northern Atlantic Forest region were determined, and analyses were conducted with single-season occupancy models. The diurnal temperature range had the most significant impact on occupancy. Climate stability and the forest area were determining factors in the large-scale occupancy of C. canadensis. Other impacts on occupancy were noted as altitude and secondary effects due to precipitation. Records of C. canadensis in the region are probably associated with multiple interaction factors. The preservation of forested and climatically stable habitats of the region should favor the establishment of forest specialist species such as C. canadensis within the study region. The more significant climatic instability present along the final portion of the Sao Francisco River, probably a consequence of the loss of forest cover, can be considered an area that requires more urgent action for the conservation of this forest specialist species. Thus, our data validate the importance of forest remnants and reinforce the adverse effects of habitat fragmentation and degradation on the requirements of endemic bird populations of the Atlantic Forest.

A new species of lizardfish, Saurida weijeni sp. nov., from deep water of the outer slope of the North Macclesfield Bank (Zhongsha), South China Sea, and Guimaras Island, Western Visayas region of the Philippines, is described and figured. The new species is distinguished by the following combination of characteristics: dorsal fin with 11-12 rays; pectorals with 13-15 rays; lateral-line scales 49-52; transverse scale rows above the lateral line 3½, below the lateral line 5½; pectoral fins moderately long (extending to or just beyond a line from origin of pelvic fins to origin of dorsal fin); 2 rows of teeth on outer palatines; 0-3 teeth on vomer; tongue with about 3-4 rows of teeth posteriorly; 47-49 vertebrae; caudal peduncle compressed (depth greater than width); anterior part of stomach dusky or black, posterior extension pale whitish, intestine black. Saurida weijeni sp. nov. is genetically distinct from all other species of Saurida.

A new species of the ostracod genus Elpidium (Timiriaseviinae), a group almost exclusively known from Neotropical bromeliad phytotelmata, is here described and illustrated from the northeast of Argentina. Elpidium chacoense n. sp. represents the first record of the genus in this country and brings the total of described Elpidium species to 19. In view of the recently increased knowledge on the distribution of the species in this Neotropical genus, we discuss potential drivers of speciation that might have led to the high (endemic) diversity of the group: allopatry in bromeliad islands, sexual selection and putative co-evolution between ostracod and bromeliad species. We also point out the biogeographical relevance of the present records, which are amongst the most southern of the genus. Finally, also the fact that species of Elpidium can now also be found in non-bromeliad phytotelmata is of relevance.

Natsushima is a genus of deep-sea Chrysopetalidae (Annelida) characterized by numerous bifurcate chaetae. It is poorly known, with three species living in the mantle cavity of bivalves in chemosynthetic habitats. Here we describe Natsushima nanhaiensis n. sp. based on an integrative morphological and molecular phylogenetic analysis of specimens collected from the Haima cold seep in the South China Sea. Morphologically, the new species can be distinguished from its congeneric species by the shape and number of the neuropodial hooks and bifurcate chaetae, the shape of the parapodia, and the long dorsal cirri. Sequence comparison and phylogenetic analysis based on the mitochondrial COI and 16S rRNA gene sequences supported the placement of Natsushima nanhaiensis n. sp. in Natsushima and its status as a distinct species. We also present a key to species of Natsushima and discuss their biogeography.

This is the first taxonomic study of Collembola in Taiwan integrating morphological and molecular evidence to investigate the Taiwanese species in the genus Ptenothrix Börner. We discovered that specimens previously identified as Ptenothrix denticulata (Folsom, 1899) actually consist of several cryptic species, of which we described two species new to science. Our data revealed that, although these species are remarkably similar to each other, they can be distinguished by color patterns, chaetotaxic characters and DNA barcoding (COI). We also designated one of the syntypes of Ptenothrix denticulata (Folsom, 1899) as its lectotype, and treated Dicyrtoma denticulata (Salmon 1964) as a synonym of Ptenothrix denticulata (Salmon 1964) (syn. nov.). Lastly, our study suggests that the diversity of Collembola in Taiwan is still poorly understood, with a high potential for new studies focusing on these microarthropods.

he Arctic warbler (Phylloscopus borealis) species complex is commonly present in the Palearctic region. By 2014, the three bird subspecies were split into three species, Arctic warbler (P. borealis), Japanese leaf warbler (P. xanthodryas), and Kamchatka leaf warbler (P. examinandus), based on different breeding areas and distinct vocalizations. However, their similar coloration and body size make it difficult to distinguish these species in the nonbreeding season. Taiwan is located in the potential migration routes of the Arctic warbler species complex; however, no confirmed record of P. xanthodryas and P. examinandus exists. In this study, we compared the mitochondrial cytochrome c oxidase subunit 1 (CO1) sequences of samples from breeding sites during the breeding season and confirmed that the three species could be distinguished based on CO1 gene sequences. We also examined the species of the Arctic warbler species complex samples collected from eastern Taiwan. For the first time, we confirmed that all three species visited Taiwan during migration season. In the Taiwanese samples, no clear distinction could be made between species based on plumage coloration and size, indicating that these traits are not reliable for species identification. Reassessment of the CO1 gene sequences of the three species deposited in the Barcode of Life Data System revealed that the taxonomic status needs to be updated for 31.8% of the samples.

The isotopic discrimination between a mother and her hatchlings has been modelled in various vertebrates, including sea turtles. In addition to the linear relation between δ¹³C and δ¹⁵N isotope values of the mother - hatchling couple, there is missing data on the combined effects of both isotopes, which represent ecological niches of a species. The stable δ¹³C and δ¹⁵N isotope signatures of live hatchlings and their mother's epidermis tissues were used in green turtles. The samples were taken from three main breeding beaches, Akyatan, Sugözü and Samandağ in Türkiye during the 2020 nesting season. δ¹⁵N and δ¹³C values of hatchlings were not significantly different from those of mothers. Significant relationships were found between hatchlings and their mothers in terms of δ¹³C value. Furthermore, when the hatchling isotopic niche size is known, the condition probabilities of estimating the mother's isotopic niche size were 85.16% and 92.88% with the 0.95 and 0.99 alpha levels. In addition to showing a linear relationship between hatchlings and their mother's single isotopic composition, the current study offers a novel insight that proposes a niche overlap concept using two isotopes to comprehend the mother-hatchling relationship of green turtles living in the eastern Mediterranean.