June 2023

Accompanying companion

A striped skunk (Mephitis mephitis) that had been killed by a vehicle in western Oklahoma was examined as part of an ongoing wildlife health survey. Two nematodes (1cm and 3.5cm in length) that had apparently been dislodged on impact were present on the fur and collected for identification.

Image 1: Nematode visible grossly on foot of skunk

​Images 2: Anterior end under 4x objective

Image 3: Anterior end under 10x objective

Image 4: Anterior end under 20x objective

Image 5: Posterior end under 10x objective

What's your diagnosis?

Physaloptera sp.
​Adult Physaloptera spp. are found in the stomach of domestic and wild carnivores. The species P. maxillaris most commonly uses skunks as the definitive host. Identification can be determined based on the presence of morphologic features including the cuticular collar and presence of two triangular pseudolips at the anterior end. The length of the body is covered by a cuticle, and the posterior end is blunted. Male Physaloptera spp. have caudal alae at the posterior end, which is useful to differentiate them from ascarid species. Intermediate hosts of Physaloptera spp. include ground beetles and crickets; other vertebrates, including mammals, amphibians, and reptiles, can serve as paratenic hosts.