First Record of an Invasive Nectar Source for Prioneris thestylis (Doubleday, 1842) (Lepidoptera: Pieridae) in Namdapha Tiger Reserve, Changlang District, Arunachal Pradesh, India

Chromolaena odorata, an invasive shrub bearing pale pink flowers, typically blooms from December to April. This study presents the first documented observation of Prioneris thestylis (Doubleday, 1842) utilizing C. odorata as a nectar source within Namdapha Tiger Reserve (27°23ʹ30ʺ N to 27°39ʹ40ʺ N and 96°15ʹ2ʺ E to 96°58ʹ33ʺ E), a 1,985 km² protected area in Changlang District, Arunachal Pradesh, India, bordering northern Myanmar. Fieldwork was conducted from September 2024 to March 2025 as part of an ongoing White-bellied Heron conservation project. Repeated observations confirmed P. thestylis feeding on C. odorata with photographic documentation and spatial mapping performed. These findings contribute to the ecological understanding of P. thestylis and highlight the potential influence of invasive flora on native butterfly foraging behavior. The study underscores the need to monitor C. odorata’s spread and its implications for pollinator dynamics in Namdapha Tiger Reserve.