The marginated tortoise Testudo marginata, native to the southern Balkans, is the largest Testudo species and shows limited sexual dimorphism. We analysed the morphological variation of 295 tortoises of a single population from the Achelous Delta (western Greece), focusing on body size, Sexual Dimorphism Index (SDI) and the Scaled Mass Index (SMI). Males were slightly larger (mean straight carapace length 27.4 cm) and heavier (mean weight 2,932 g) than females (26.0 cm, 2,627 g), with an SDI value of -0.051 indicating that males are larger than females by 5.1%. However, the largest individual was a female (38 cm straight carapace length) and the SMI was similar for males (4.74) and females (4.79). The species preferred open habitats with low forest cover, and although both sexes used areas with high herbaceous cover, males occupied more shrub-rich plots while females used more sparsely vegetated habitats.
In September 2025, the fourth Vanishing Viper conference was held to maintain focus on the conservation of the northern viper or adder Vipera berus, a species subject to significant population declines and local extirpations in Britain. Compared to previous conferences in the series, Vanishing Viper 2025 considered a wider range of topics including: genomics, process-based modelling, habitat management, translocations, the role of volunteer work, and included the unveiling by Amphibian and Reptile Conservation Trust of a national strategy document that offers guidance on conservation translocations for viper recovery. The discussions following these many topics were wide-ranging and included some cautions that our current understanding of viper genetics is still inadequate to support the safe use of genetic rescue of populations considered to be inbred. There were also two workshops, one examining what defines disturbance for vipers and the other considering the role and challenges of conservation translocations, these are both presented in more detail in Supplementary Material. The rise in conservation actions for V. berus at the landscape-level gives cause for some optimism that conservation outcomes will be increasingly successful.
