Myzostomida

Myzostomida
Myzostoma fuscomaculatum on its host the crinoid Tropiometra carinata
Scientific classification
Kingdom: Animalia
Phylum: Annelida
Clade: Pleistoannelida
Order: Myzostomida
von Graff, 1877

The Myzostomida or Myzostomatida are an order of small marine worms, which are parasitic on echinoderms, mostly crinoids. These highly unusual and diverse annelids were first discovered by Friedrich Sigismund Leuckart in 1827.