Proleptus obtusus Dujardin, 1845 (Nematoda: Physalopteridae) from the puffadder shyshark Haploblepharus edwardsii (Scyliorhinidae) from off South Africa.

Specimens of the physalopterid nematode Proleptus obtusus Dujardin, 1845 collected from the intestine of the puffadder shyshark Haploblepharus edwardsii (Voigt) off De Hoop Nature Reserve, Cape Province, South Africa, made possible the redescription this little-known species. The SEM study of the cephalic end revealed the presence of circumoral denticles and some oral structures (lateral transverse mounds on the inner surface of pseudolabia, dorsolateral and ventrolateral band-like formations or lamellae surrounding the buccal cavity) not previously reported for any species of Proleptus. The shape of the tip of the right spicule is considered to be the only reliable feature for differentiating P. obtusus from the closely related P. acutus Dujardin, 1845. The finding of the former in H. edwardsii represents a new host record.