Ultraviolet irradiation alters the density of inner mitochondrial membrane and proportion of inter-mitochondrial junctions in copepod myocytes

•Mitochondrial behavior and morphology influence whole-animal performance.•Environmental stressors influence mitochondrial behavior and morphology.•Ultraviolet irradiation alters mitochondrial behavior, morphology, and metabolic rate.•Understanding variation in mitochondrial structure and behavior may provide insight into understanding animal performance.