|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Palaeoscolecida - Cricocosmida - Palaeoscolecidae
If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
|A. Y. Ivantsov and R. Wrona 2004||Cylindrical cuticle of worm with closely spaced annulation. Intercalations lacking. Annuli with one or two rows of plates widely arranged, and no platelets nor microplates. Plates vary in size and ornamentation, circular to oval-shaped, with strongly convex upper surface covered by 4-10 (usually 6) sharp cones, often protruding as spines arranged in circle or rows, sometimes also with a central node. Plates with spiny ornament are grouped on the ventral side of the trunk.|