Oesophagostommum (Oesophagostomum) dentatum   
Fig. 1: Anterior end, showing corona radiatae, cervical groove, and a pair of cervical papillae
Fig. 2: Posterior end of male, showing spicules, a pair of prebursal papillae and arrangement of rays in bursa
Fig. 3: Posterior region of female, showing opening of vulva and anus
Fig. 4: Egg