Scavengers at risk: predicting the distribution of Blaps polychresta (Coleoptera: Tenebrionidae) amidst climate change

Blaps polychresta, a nocturnal scavenger beetle endemic to North Africa, plays an essential role in nutrient recycling within agricultural ecosystems. This study employs species distribution models (MaxEnt and DIVA-GIS) integrated with geographic information systems (GIS) to assess current and future distributions of B. polychresta in Egypt under climate change scenarios. We analysed five bioclimatic variables alongside topographic data to forecast habitat suitability under RCP 2.6 and RCP 8.5 scenarios for 2050 and 2070. Our models reveal that B. polychresta currently occupies approximately 145,250 km2 of suitable habitat, concentrated in northern and eastern Egypt. Climate projections indicate substantial habitat loss: 22.6% by 2050 and 32.0% by 2070 under RCP 2.6, escalating to 38.5% and 56.5%, respectively, under RCP 8.5. Highly suitable habitats face disproportionate reductions of 74.2% by 2070 under the high-emission scenario, with the Nile Delta losing 68% of suitable areas. These findings underscore the vulnerability of B. polychresta as a soil health bioindicator and highlight the urgent need for conservation strategies to protect this ecologically important species. Our study demonstrates the critical role of geospatial technologies in understanding ecological responses to climate change and informing biodiversity conservation efforts.