Definition: Protoglomeridae is a group of protogynous glomerular animals, including the common rabbit glomerulovessus and other related species. These animals play crucial roles in maintaining blood pressure within the body by regulating the flow of blood through the renal system. Protoglomeridae are unique because they have an eggshell-like structure that helps to protect the eggs during fertilization, which is a crucial step for their survival and growth.