Altitudinal wing shape variation in Bombus haemorrhoidalis Smith, 1852 and Bombus tunicatus Smith, 1852 (Hymenoptera: Apidae) from the Kashmir Valley, India: a geometric morphometric approach

Understanding morphological adaptations of pollinators is key to studying their ecology, especially in topographically diverse regions like the Kashmir Valley. This study investigates wing shape variation in two bumble bee species, B. haemorrhoidalis and B. tunicatus, collected across distinct altitudinal sites in Jammu and Kashmir, India. Using landmark-based geometric morphometrics, 19 landmarks were digitised on forewings of worker bees. Principal Component Analysis (PCA), Canonical Variate Analysis (CVA), Mahalanobis and Procrustes distances revealed statistically significant differences in wing shape between populations. Wing variation across elevation gradients indicate localised morphological adaptations. These insights support future investigations into the evolution, ecology and conservation of Bombus species in the Western Himalayas.