develops from spermatheca fly_anatomy.ontology Mushroom-shaped organ consisting of a capsule surrounded by secretory cells, connected to the dorsal side of the uterus by a slender duct, which protrudes into the capsule to form an introvert (Heifetz and Rivlin, 2010; Mayhew and Merritt, 2013; McQueen et al., 2022). The capsule is lined by a sclerotized cuticular intima (Mayhew and Merritt, 2013), which is produced by the secretory cells (Miller, 1950; McQueen et al., 2022). Each secretory cell wraps around a specialized cuticle-like structure called an end-apparatus, which is connected to the intima by a duct (Mayhew and Merritt, 2013). Sperm is stored in this organ after mating; it stores fewer sperm that the seminal recepticle, but retains them for a longer period of time (Heifetz and Rivlin, 2010; McQueen et al., 2022). There are two spermathecae per female (Heifetz and Rivlin, 2010; Mayhew and Merritt, 2013; McQueen et al., 2022). FBbt:00004921 spermathecae spermathecum UBERON:0000994 epithelial tube female reproductive gland sperm storage organ presumptive spermatheca