Alpha diversity with increasing altitude and Rapoport’s rule adherence: Elevational trends in Noctuoidea (Lepidoptera) of Mizoram, India

An assessment of the alpha diversity across the altitudinal range sizes for the moths of Noctuoidea (Lepidoptera) collected from 25 locations in Mizoram, a biodiversity hotspot in India, was undertaken. A total of 164 moth specimens were examined. based on morphological and genitalia characteristics for their identity. Identified specimens belonged to 42 species and 34 genera of three families Erebidae, Noctuidae and Nolidae. The results showed that the alpha diversity of Noctuoidea moths was the highest at the lower middle altitude range (400-800 m), while the least was at the lower elevation range (0-400 m). In contrast, the species' ranges increased with rising altitude. Steven's (R = 0.903, p < 0.001), Pagel's (R² = 0.873, p < 0.06), Rohde's (R² = 0.961, p < 0.001) and cross-species (R² = 0.013, p < 0.6) methods were used to test Rapoport's rule. They yielded three positive results with the cross-species method being negative due to outliers in the species distribution. Rapoport's rule applicability for moths in the Indo-Myanmar biodiversity hotspot was evaluated for the first time. These findings are vital in explaining the elevational diversity patterns of noctuoid moths in northeast India and Indo-Myanmar, leading to a better understanding of the region's biogeography.