Heterodera is a

Heterodera is a Sedentary endoparasite.
Heterodera is a genus of nematodes in the family of Heteroderidae. The genus is unique among nematode genera because of the ability of the female to transform into a tough, brown, cyst that protects the eggs which have been formed within her body.
The cyst nematodes (Heterodera and Globodera) and root-knot nematodes (Meloidogyne) are sedentary endoparasites within a broad group of free-living and parasitic worms.