Abstract
This study reports new locality records from Iran and a climate-based habitat suitability assessment for Sassanidotus gracilis (Birula, 1900) (Scorpiones: Buthidae) in the Iran–Afghanistan–Pakistan arid belt. We document new specimens from Sistan and Baluchestan Province, Iran, with an updated distribution map and illustrations, and we model the species' potential distribution across south-eastern Iran and adjacent parts of Afghanistan and Pakistan.
Habitat suitability was associated mainly with precipitation seasonality, precipitation of the wettest month, precipitation of the driest month, and slope. In an arid setting these rainfall variables are unlikely to indicate a need for moist habitat; they more plausibly track seasonal productivity and the terrain features that provide shelter. Present-day suitable areas were concentrated in south-eastern Iran, particularly Sistan and Baluchestan, and extended into south-western Afghanistan and western Pakistan.
Projections under SSP1-2.6, SSP3-7.0 and SSP5-8.5 indicated that suitable habitat persists across most core areas but is redistributed over time. Net change was small and negative under every scenario, from about −0.4% to −7.0% of the present suitable area, with the largest reduction under SSP5-8.5 for 2071–2100. These net values were accompanied by high spatial turnover: even in the near-future period about 44% of the present suitable area was reclassified as unsuitable while a comparable area became newly suitable. Disagreement among climate models was large and grew with time and emission level (mean coefficient of variation 28–75%), so the net changes are of similar or smaller magnitude than the projection uncertainty and should be read as evidence of spatial reorganization rather than precise area loss.
The species therefore seems likely to keep much of its suitable habitat, although the high-emission scenario points to more fragmentation late in the century. Because a dispersal-limited scorpion may have limited ability to rapidly reach newly suitable areas, the predicted areas are best treated as hypotheses for survey rather than forecasts of occupancy. They identify priority targets in poorly sampled parts of south-eastern Iran, western Pakistan and adjacent Afghanistan.
Recommended Citation
Yağmur, E. A., Çiçek, K., Barati, H., & Moradi, M. 2026 . New locality records and future habitat suitability of Sassanidotus gracilis (Birula, 1900) (Scorpiones: Buthidae) in the Iran–Afghanistan–Pakistan arid belt. Euscorpius, No. 440: 1-19.
