Secernentea
Secernentea was a class of nematodes in the Classical Phylogeny System and is no longer in use. This morphological-based classification system has been replaced by the Modern Phylogeny system, where taxonomy assignment is based on small subunit ribosomal DNA.
Description
Amphid apertures of Secernenteas are pore or slit-like.Some Secernenteas have deirids which are located near nerve ring.
Secernenteas have posterior phasmids.
The excretory system of a Secernentea is tubular.
Cuticles of Secernenteas are striated in two to four layers. Lateral field is present.
Secernenteas have three esophageal glands. Their esophageal structure varies.
Male Secernenteas generally have one testis.
Caudal alae are common in Secernenteas.
Sensory papillae of Secernenteas are cephalic only. It might be caudal papillae in male Secernenteas.
Secernenteas are mostly found in land but they are rarely found in marine water or freshwater.
Taxonomy
Subclasses and orders of Secernentea are:- Subclass Rhabditia
- * Rhabditida
- * Strongylida
- Subclass Spiruria
- * Ascaridida
- * Camallanida
- * Drilonematida
- * Oxyurida
- * Rhigonematida
- * Spirurida
- Subclass Diplogasteria
- * Diplogasterida
- Subclass Tylenchia
- * Aphelenchida
- * Tylenchida