The process of testicular regression also impacts the physiology of the epididymis of the bat Molossus molossus, although with a delay in epididymal response due to sperm storage

•Sperm storage causes delay in epididymal response to the testicular regression.•The epididymis of M. molossus has a large predominance of principal and basal cells.•Epididymal seasonal variations are correlated to rainfall and photoperiod.•Epididymis of M. molossus are regulated by the AR expression in epithelial cells.