Progress on reproductive modes of sarcosaphagous flies

Abstract The reproduction strategies of invertebrates, oviparity, ovoviviparity and viviparity, always reflect the relationship between individuals and their surroundings. There is plasticity in the reproductive strategies of sarcosaphagous flies as they adjust to rapidly changing circumstances. The transition from oviparity to ovoviviparity or viviparity involves numerous changes in physiology, morphology and immunology. Demonstrating these processes can make the application of entomology work in forensic practice more reliable. This essay reviews means of reproduction in sarcosaphagous flies and identifies related features. It is shown that not only the reproduction traits, such as fast location of carrion, and uncommon number of ovaries and oogenesis, but also some morphological features are related to viviparity. In general, viviparous flies have larger adult bodies but smaller eggs and chorions. Moreover, the length of terminalia and the shape of the vagina also varies among those three modes. Reproductive plasticity is a bridge between the three reproductive modes, and it can greatly influence the inference of the post-mortem interval (PMImin).