The Sand Worms (Phylum Gnathostomula)
- Description of the tiny marine worms in this phylum and the characteristics that distinguish them from other worms.
- http://www.earthlife.net/inverts/gnathostomula.html

The Taxonomicon: Phylum Gnathostomulida
- List of published resources on the taxonomy of this phylum.
- http://sn2000.taxonomy.nl/Taxonomicon/TaxonReferences.aspx?id=12887&tree=0.1&syn=1

Animalia - Gnathostomulida
- Diagram of a representative body plan of a gnathostomulid.
- http://biodidac.bio.uottawa.ca/thumbnails/filedet.htm?File_name=Gnat002b&File_type=gif

Phylum Gnathostomulida
- Images of some members of this taxonomic group.
- http://animaldiversity.ummz.umich.edu/site/accounts/pictures/Gnathostomulida.html