Two new species belonging to the Nippostrongylinae (Heligmosomoidea-Heligmonellidae) are described: Neoheligmonella dielmensis n.sp. and Heligmonina bignonensis n.sp. are parasites of Arvicanthis niloticus and Mastomys huberti, respectively. N. dielmensis n.sp. differs from the other species of the genus by its synlophe pattern at mid-body and vulval level, by the ratio between the height and the breadth of the caudal bursa and that of the length of the spicules and the length of the body. H. bignonensisH. chabaudi (Durette-Desset, 1964), a parasite of Muridae from the Central African Republic, its female possesses a very short ovejector and a straight tail. It is distinguished by the shape of the tip of the left ridge in transverse section (sharp and not round), by the narrowness of rays 8 and by the short distance between the vulva and the anus.
Neoheligmonella dielmensis n.sp., Heligmonina bignonensis n.sp., Nematoda, Trichostrongylina, Nippostrongylinae, Muridae, rodents, Senegal.