Ecdysozoa orders

order of tardigrades

Echiniscoidea is an order of tardigrades, a phylum of water-dwelling, eight-legged, segmented micro-animals. It was first described by Richters in 1926.

Arthrotardigrada are an order of tardigrades, first described by Ernst Marcus in 1927.

Gordioidea is an order (sometimes placed at superfamily level) of parasitic horsehair worms. Its taxonomy remains uncertain, but appears to be contained in the monotypic class Gordioida and contains about 320 known species.

Priapulimorphida is the sole order within the Priapulimorpha, one of the three extant priapulid classes.