Spirurida

Spirurida falls under the phylum Nematoda class Chromadorea and order Rhabditida. They are characterized by their elongated, cylindrical bodies and unsegmented structure. Like all nematodes, they have neither a circulatory nor a respiratory system.

Spirurida
Dirofilaria immitis larva Magnification 400×
Scientific classification
Kingdom:	Animalia
Phylum:	Nematoda
Class:	Chromadorea
Order:	Rhabditida
Suborder:	Spirurida
Superfamilies
10, but see text

Some Spirurida, like the genus Gongylonema, can cause disease in humans. One such disease is a skin infection with Spirurida larvae, called "creeping disease". Some species are known as eyeworms and infect the orbital cavity of animal hosts.

Systematics

The Camallanida are sometimes included herein as a suborder, and the Drilonematida are sometimes placed here as a superfamily. There are doubts about the internal systematics of the Spirurida, and some groups placed herein might belong to other spirurian or even secernentean lineages.^[1]

The following superfamilies are at least provisionally placed in the Spirurida:

• Acuarioidea
• Aproctoidea
• Diplotriaenoidea
• Filarioidea
• Gnathostomatoidea
• Habronematoidea
• Physalopteroidea
• Rictularioidea
• Spiruroidea
• Thelazioidea