Gnathostomulids

Gnathostomulids, or jaw worms, are a small phylum of nearly microscopic marine animals. They inhabit sand and mud beneath shallow coastal waters and can survive in relatively anoxic environments. They were first recognised and described in 1956.

Bursovaginoidea is one of the two orders in the phylum Gnathostomulida.

Filospermoidea is an order within the phylum Gnathostomulida. Filospermoids are generally longer than gnathostomulids in the order Bursovaginoidea, and have an elongate rostrum. It lives in North America, off the coasts of the southern United States and the Caribbean, primarily in the Gulf of Mexico, as well as in southeastern Denmark.

Onychognathiidae is a family of worms belonging to the order Bursovaginoidea.

Cosmognathia is a genus of worms belonging to the family Pterognathiidae.

Mesognathariidae is a family of worms belonging to the order Bursovaginoidea.

Haplognathiidae is a family of worms belonging to the order Filospermoidea.

Agnathiellidae is a family of worms belonging to the order Bursovaginoidea.

Gnathostomulidae is a family of worms belonging to the order Bursovaginoidea.

Austrognathiidae is a family of worms belonging to the order Bursovaginoidea.

Pterognathiidae is a family of worms belonging to the order Filospermoidea.

Haplognathia is a genus of worms belonging to the family Haplognathiidae.

Rastrognathia is a monotypic genus of worms belonging to the monotypic family Rastrognathiidae. The only species is Rastrognathia macrostoma.

Paucidentula is a monotypic genus of worms belonging to the monotypic family Paucidentulidae. The only species is Paucidentula anonyma.

REDIRECT Rastrognathia

Clausognathiidae is a family of worms belonging to the order Bursovaginoidea.

Gnathostomariidae is a family of worms belonging to the order Bursovaginoidea.

Pterognathia is a genus of worms belonging to the family Pterognathiidae.

REDIRECT Paucidentula

REDIRECT Problognathia

Problognathia is a monotypic genus of worms belonging to the monotypic family Problognathiidae. The only species is Problognathia minima, also known as the problematic jaw worm.