Foetal membranes and placenta of the springhare (Pedetes capensis larvalis Hollister)

Abstract

The foetal membranes and placenta of the East African springhare from the embryonic disc stage to mature stage are described. Implantation is superficial and central. A massive preplacenta is evident before the chorioallantoic placenta is formed. The parietal trophoblast persists throughout pregnancy. No inversion of the yolk sac (or germ layers) occurs in the East African springhare. The placental barrier is essentially endotheliochorial, consisting of maternal capillary endothelium with a prominent acidophilic PAS positive lamina and a layer of syncytial trophoblast. This study also demonstrates a close similarity of the springhare to the rest of the rodents in foetal membranes and placental structures. On the basis of foetal membranes and placenta development the East African springhare is more closely related to the scuiromorphs than to the other suborders. The springhare should be placed in its own superfamily of Pedetoidea in the suborder scuiromorpha.