Abstract
Background:
Apis dorsata is one of the most economically important bees. The A. dorsata colonies are rapidly declining in Pakistan due to multiple factors. Investigation regarding Varroa destructor in A. dorsata was completely ignored in the past.

Aim:
This study aimed to investigate the morphological identification, prevalence, and infestation rate of V. destructor in the phoretic phase and reproductive phase of A. dorsata in Pakistan.

Methods:
This research was performed season-wise from December 2022 to November 2023 in the selected districts of Khyber Pakhtunkhwa, Pakistan. Season-wise (one month of each season) examination of A. dorsata hives, samples collection, and examination of adult and sealed brood cells of A. dorsata for V. destructor collection, morphological identification, prevalence, and infestation rate was carried out. The data were analyzed by ANOVA and t-test.

Results:
The different life stages of V. destructor were identified based on morphological characters. Sizes of protonymph, deutronymph , and adult female V. destructor were 631–682 × 735–784 μm, 1,011–1,197× 1,080–1,667 μm, and 1,168–1,205 × 1,741–1,785 μm, respectively, while male V. destructor were 598–626 × 605–661 μm, 739–787 × 706–741 μm and 801–870 × 803–874 μm, respectively. In winter, spring, summer, and autumn, the prevalence of V. destructor in the phoretic phase of A. dorsata was 36%, 60%, 44%, and 32%, respectively, whereas in the reproductive phase was 4%, 32%, 60%, and 48%, respectively. Seasonal prevalence of V. destructor showed a statistically significant effect (p <0.05) in the phoretic and reproductive phases of A. dorsata. A comparative prevalence of V. destructor between phoretic and reproductive phases of A. dorsata colonies was found highly significant (p <0.05) in winter and spring. The overall prevalence of V. destructor in A. dorsata colonies in winter, spring, summer, and autumn was 36%, 60%, 60%, and 48%, respectively. The comparative infestation rate of V. destructor between phoretic and reproductive phases was found highly significant (p < 0.05) in winter, summer, and autumn. Season-wise overall infestation rate of V. destructor showed significant results (p < 0.05) in the phoretic and reproductive phases.

Conclusion:
The infestation of V. destructor was first time recorded in A. dorsata. This parasite continuously declines the A. dorsata in Pakistan.

Key words: Honeybee, Invasion, Mite, Pathogen, Varroosis