Lipofuscin accumulation (black granular structures: arrows) in the hypopharyngeal glands of nurse and forager bees A A. m. carnica nurse B A. m. carnica forager C A. m. jemenitica nurse D A. m. jemenitica forager E A. m. ligustica nurse F A. m. ligustica forager. (Images at 400× magnification).

  Part of: Ali H, Alqarni AS, Iqbal J, Owayss AA, Raweh HS, Smith BH (2019) Effect of season and behavioral activity on the hypopharyngeal glands of three honey bee Apis mellifera L. races under stressful climatic conditions of central Saudi Arabia. Journal of Hymenoptera Research 68: 85-101.