We review the systematics of the Madagascar-endemic frogs of the genus Spinomantis based on DNA sequences of mitochondrial and nuclear-encoded genes from 368 individuals. We find the arboreal species in the genus, the focus of this study, to form a well-supported clade in a mitochondrial multi-gene tree, containing three subclades, here named the peraccae dade, the aglavei clade, and the massi dade. Each of these contained numerous deep mitochondrial lineages differing by at least 3.1% uncorrected pairwise distance in a fragment of the mitochondrial 16S rRNA gene. Our preferred partition distinguishes 20 mitochondrial species-level lineages in the arboreal Spinomantis clade, including seven nominal species, four new species described herein, and nine additional candidate species that require further study. The four new species described herein are delimited by a combination of several lines of evidence, including high divergence in mitochondrial DNA (> 3.5% 16S divergence to nominal species), isolated phylogenetic position, differentiation in nuclearencoded gene fragments, and morphological and bioacoustic divergence: S. chlorostictus sp. n. is a species of the peraccae clade primarily from northern Madagascar differing by color pattern and bioacoustics from S. peraccae; S. royae sp. n. and S. leonieae sp. n., belonging to the aglavei clade, are morphologically similar to S. fimbriatus but differ by color pattern and advertisement call; and S. fohitsilo sp. n. is morphologically similar to S. massi but not that species' direct sister group, and differs by its advertisement call. Our study provides a baseline for understanding the diversity and biogeography of Spinomantis, highlights the enormous amount of yet unexplored amphibian diversity in Madagascar, and points to geographical regions and taxa where further field exploration, including the collection of voucher specimens and of bioacoustic data, is needed to complete the herpetofaunal inventory of the island.
The Eutropis multicarinata species complex comprises lineages that have diversified genetically across the Philippine archipelago and nearby islands, largely without corresponding phenotypic differentiation in external morphology. Although recent work has clarified the systematics and evolutionary history of most members of the complex, their relationship to E. englei, a poorly known and enigmatic species from south-central Mindanao, has remained phylogenetically unresolved since the original description of the species. For the first time in 100 years since its first (and only) known collection, we collected new specimens and fresh tissue samples of E. englei and assembled a DNA sequence dataset to determine its phylogenetic placement. Unexpectedly, our multilocus phylogeny recovers E. englei as the sister taxon to E. palauensis, a species endemic to the Palau archipelago (-1,500 km to the east), with shallow genetic divergence (3-4% based on concatenated sequences) - the lowest interspecific genetic distance documented within the E. multicarinata complex. The new specimens also reveal sexual dimorphism in size and coloration not previously reported in earlier work on this species. We briefly discuss biogeographic implications of these findings and identify priorities for future research. This work helps fill a long-standing phylogenetic gap in Philippine reptile systematics and underscores the urgent need for targeted wildlife genetic sampling, especially in species' type locality or other hard-to-access specific sites, enabled by collaborative, collections-based fieldwork.
Predatory behavior modification is related to physiological and/or environmental factors. Understanding how these factors influence predation success in dynamic ecosystems, whether as a result of natural variations or anthropogenic changes, can provide information to elucidate population responses in a changing world. In aquatic environments, prey availability and the physiological signals associated with predatory behavior are linked to changes in water temperature. We examined predatory behavior and predation performance of A. dumerilii during critical larval and juvenile stages (i.e., first 10 weeks of life), at different temperature regimes. The objective was to identify the optimal temperature for prey consumption and predation efficiency under controlled conditions. The experimental design included three temperature treatments (18 degrees C, 21 degrees C, and 25 degrees C) with five replicates each, and a 12/12 photoperiod. Encounters, attacks, captures, ingestions, rejections, and prey escapes were quantified using video recordings and direct observations. Results showed that at 18 degrees C, individuals displayed significantly higher activity levels and improved predation success, whereas higher temperatures (21 degrees C and 25 degrees C) reduced both activity and predation efficiency. Our results also showed that the per capita growth rates were lower at the highest temperature. These findings suggest that the increase in temperature can reduce growth rates, subsequently limiting the ability of the predator to consume prey. Regarding temperature changes in aquatic ecosystems related to global warming, our results provide valuable insights for identifying priority conservation areas, thereby promoting the preservation of A. dumerilii and the trophic networks.
Turtles and tortoises are one of the most endangered groups of vertebrates, especially in Asia, a hotspot for reptile biodiversity. Roadkill can pose an additional threat that may affect the long-term persistence of turtle populations. The aim of this study is to assess the viability of the populations of three threatened species of turtle, the Spur-Thighed Tortoise Testudo graeca (VU), the Southeast Asian Box Turtle Cuora amboinensis (EN) and the Elongated Tortoise Indotestudo elongata (CR), in five areas in Asia. We developed a spatially implicit model using demographic parameters of each species and estimated roadkill rates (ind/km/year) to predict how the populations will evolve in the next 20 years with the assumption that the observed roadkill persists. We also estimated the proportion of mortality necessary to lead these populations to local extinction. Roadkill as an additional source of mortality is unlikely to impact the studied populations. Approximately 50% of annual mortality is necessary for the populations to no longer be viable. Unexpectedly, conservation status had no significant effect on the degree to which species are impacted by roadkill. Only Southeast Asian Box Turtle populations decreased drastically, not due to roadkill, but most likely because of the low recorded adult survival rates. Future research should focus on better understanding the influence of other threats in combination with roadkill, as well as doing more population studies that consider the specific demographic parameters of local populations of turtles.
We inferred the distribution ranges of two subspecies of the barred grass snake (Natrix helvetica helvetica, N. h. sicula) and the common grass snake (Natrix natrix vulgaris) in western Austria and adjacent Bavaria (Germany) using coloration and pattern traits of 943 georeferenced photographic records from the citizen science platforms iNaturalist and Observation.org. Accordingly, the nominotypical subspecies of the barred grass snake is distributed in the Walgau, Montafon, and Klostertal regions of Austria (Vorarlberg), while N. n. vulgaris prevails in the Rhine Delta and the eastern Lake Constance area. However, a few grass snakes in the latter regions, including in Bavaria the district of Lindau (Bodensee) at Lake Constance, are putative hybrids or pure N. h. helvetica. The range of N. h. helvetica in the Klostertal is separated by the Arlberg region and a most likely less than 40-km-wide gap from the distribution of N. h. sicula in the Inn drainage in Tyrol (Austria). All records from the catchment systems of the Isel and Salzach rivers (eastern Tyrol and Salzburg, Austria, respectively) were identified as N. n. vulgaris, except for a single observation of N. h. sicula at the border between Salzburg and Bavaria and a few questionable hybrids in the Salzach drainage. Natrix helvetica sicula reached southern Bavaria from northern Tyrol along the rivers Loisach, Isar, Gro ss ache, and Inn. Its range abuts with that of N. n. vulgaris in southern Bavaria and in the border region of the Austrian states Tyrol and Salzburg and near Reutte (Tyrol), where representatives of both species and hybrids were recorded. The northernmost native records of N. h. sicula or hybrids in Bavaria are near Rosenheim and Lake Chiemsee. Other Bavarian records represent N. n. vulgaris.
