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Microplastics pollution in freshwater systems is attracting increasing attention. However, our knowledge of its combined toxicity with heavy metals is scarce. In this study, Rana zhenhaiensis was used as the model animal to study the combined poisoning mechanism of cadmium or microplastics on the digestive systems of tadpoles in freshwater. Results showed that the exposure to cadmium and polystyrene increased the mortality and metamorphosis rate of R. zhenhaiensis tadpoles, and delayed their growth and development. Cadmium was detected in the livers and intestines, while polystyrene mainly accumulated in the gills and intestines of tadpoles. The individual exposure of cadmium or polystyrene can cause pathological damage to liver tissue, induce oxidative stress in liver, and change gene expression. Cadmium co-exposure with polystyrene can reduce the cadmium accumulation in the liver. While polystyrene can slightly increase cadmium accumulation in the intestine. Exposure to cadmium and polystyrene altered the abundance and community structure of intestinal microbiota, and polystyrene increased the dysregulation of the gut microbiome. In this study, the combined exposure of microplastics and cadmium had a negative impact on R. zhenhaiensis tadpoles, but the introduction of microplastics on the toxicity of cadmium on the tadpoles needs further investigation, due to the different characteristics of microplastics. [ABSTRACT FROM AUTHOR]

This article examines the role of embryonic behavioral thermoregulation in turtle hatchlings. The study conducted experiments using turtle embryos and hatchlings to investigate the effects of manipulating embryo thermotaxis. Contrary to the hypothesis that thermotaxis represents play behavior, the results showed that embryonic behavioral thermoregulation did not significantly impact the thermoregulatory behavior of hatchlings. However, the study suggests that this behavior benefits both embryos and offspring by improving developmental success and affecting offspring sex ratios. Further research is needed to understand the influence of embryonic behavioral thermoregulation on younger hatchlings. [Extracted from the article]

Despite the importance of maternally selected nests in shaping offspring phenotypes, our understanding of how the nest environment affects embryonic development and offspring traits of most non‐avian reptiles is rather limited largely due to the logistical difficulty in locating their nests. To identify the relative contributions of environmental (temporal [seasonal] and spatial [nest‐site]) and intrinsic (clutch) factors on embryonic development and offspring traits, we conducted a cross‐fostering experiment by swapping eggs between maternally‐selected nests of the toad‐headed agama (Phrynocephalus przewalskii) in the field. We found that nest environment explained a large proportion of variation in incubation duration, hatching success, and offspring size and growth. In contrast, clutch only explained a small proportion of variation in these embryonic and offspring traits. More significantly, compared with spatial effects, seasonal effects explained more phenotypic variation in both embryonic development and offspring traits. Eggs laid early in the nesting season had longer incubation durations and produced smaller hatchlings with higher post‐hatching growth rates than did later‐laid eggs. Consequently, hatchlings from early‐laid eggs reached larger body sizes prior to winter. In addition, we found that female toad‐headed agama did not select nests specific to reaction norms of their own offspring because hatchlings from original or translocated nests had similar phenotypic traits. Overall, our study demonstrates the importance of seasonal variation in nest environments in determining embryonic development and offspring phenotypes, which has not been widely appreciated at least in non‐avian reptiles. [ABSTRACT FROM AUTHOR]

We sequenced the complete mitochondrial genome ofGekko chinensis, which is an endemic species to China. The complete mitogenome is 17,906 bp in size, containing 37 genes coding for 13 proteins, two ribosomal RNAs, 22 transfer RNAs, and a control region. The A + T content of the overall base composition of H-strand is 61.1% (T: 27.6%, C: 25.5%, A: 33.5%, and G: 13.4%). The major non-coding region (control region) is 2530 bp in length and the A + T content is 67.9%. Besides, four tandem repeats were found within the control region. In Bayesian inference (BI), maximum likelihood (ML) and maximum parsimony (MP) trees, we foundG. chinensisis a sister clade toGekko swinhonis. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genomes of the yellow-bellied slider (Trachemys scripta scripta) and anoxia tolerant red-eared slider (Trachemys scripta elegans) turtles were sequenced to analyze gene arrangement. The complete mt genomes ofT. s. scriptaandeleganswere circular molecules of 16,791 bp and 16,810 bp in length, respectively, and included an A + 1 frameshift insertion in ND3 and ND4L genes. The AT content of the overall base composition ofscriptaandeleganswas 61.2%. Nucleotide sequence divergence of the mt-genome (p distance) betweenscriptaandeleganswas 0.4%. A detailed comparison between the mitochondrial genomes of the two subspecies is shown. [ABSTRACT FROM PUBLISHER]

The complete mitochondrial genome sequence of theHyla annectans(Anura: Hylidae) was determined in this study. It is a circular molecule of 17,973 bp in length including 37 genes for 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs and a control region, showing a typical neobatrachian-type arrangement. The A + T content of H-strand and the control region is 60.7% and 64.6%, respectively. The control region is 2554 bp in length and possesses distinct repeat regions at both 5′ and 3′ ends. [ABSTRACT FROM PUBLISHER]