Genomic data revealed inbreeding despite a geographically connected stable effective population size since the Holocene in the protected Formosan Long-Arm Scarab beetle, Cheirotonus formosanus

Abstract

Biodiversity conservation is a top priority in the face of global environmental change, and the practical restoration of biodiversity has emerged as a key objective. Nevertheless, the question of how to effectively contribute to biodiversity restoration and identify suitable systems for such efforts continues to present major challenges. By using genome-wide SNP data, our study revealed that populations from different mountain ranges of the Formosan Long-Arm Scarab beetle, a flagship species that receives strict protection, exhibited a single genetic cluster with no subdivision. Additionally, our result implied an association between the demographic history and historical fluctuations in climate and environmental conditions. Furthermore, we showed that, despite a stable and moderately-sized effective population over recent history, all the individuals we studied exhibited signs of genetic inbreeding. We argued that the current practice of protecting the species as one evolutionarily significant unit remains the best conservation plan and that recent habitat change may have led to the pattern of significant inbreeding. We closed by emphasizing the importance of conservation genetic studies in guiding policy decisions and highlighting the potential of genomic data for identifying ideal empirical systems for genetic rescue, or assisted gene flow studies.

DNA barcoding reveals a taxonomic fraud: Note on validity of Propomacrus muramotoae (Coleoptera, Scarabaeidae)

“… cypriacus , as a wider range correlates with greater genetic diversity in close congeners ( Cole 2003 ; Leffler et al 2012 ; Hague and Routman 2016 ). Furthermore, existing studies of the genus Cheirotonus , which is closely related to Propomacrus ( Yu et al 2023 ), demonstrate significant intraspecific variation in genetic diversity correlated with its species’ distribution patterns: Cheirotonus gestroi Pouillaude, 1913, which has a wide distribution, shows a broad range of genetic variation ( Yang et al 2020 ), in contrast to Cheirotonus formosanus Ohaus, 1913, which has a narrower distribution and exhibits lesser genetic variation ( Huang et al 2024 ). It is particularly unconvincing that individuals found with the labels “Nepal” and “Tibet” possess a COI haplotype identical to the most common haplotype identified in Turkey populations, raising suspicions about the uniformity of sequences between the individuals.…”