Secernentea

Secernentea is a class of nematodes, which are small, typically microscopic, parasitic worms. They are distinguished by having a specialized tubular excretory system with three canals. The Secernentea are further divided into two subclasses: the Rhabditia and the Spiruria.

Characteristics

Secernentea are characterized by their three-canal excretory system and a specialized stoma, or mouth, which is often surrounded by sensory structures called papillae. They also have a unique phasmid, a sensory organ, located near the posterior end of the body.

Subclasses

Secernentea is divided into two subclasses: Rhabditia and Spiruria.

Rhabditia

Rhabditia includes many free-living species as well as some parasitic ones. They are characterized by a rhabditoid pharynx, a type of muscular throat used for feeding.

Spiruria

Spiruria are primarily parasitic and are characterized by a spirurian pharynx. They often have complex life cycles involving multiple hosts.

Ecology

Secernentea species are found in a wide range of environments, from soil to fresh and salt water. Some species are parasitic, infecting a variety of hosts including humans, animals, and plants.

Medical relevance

Some Secernentea species are of medical and veterinary importance due to their parasitic nature. For example, species in the genus Strongyloides can cause strongyloidiasis, a disease in humans and other mammals.

See also

• Nematode
• Parasitism
• Strongyloides

Secernentea

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  C. elegans wild type with nhr-80 RNAi