|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
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.
|G. E. Budd 1995||Trilobite-like arthropod with ogival cephalic region probably containing five segments, one of which is occipital. Parallel-sided and trilobed thoracic region with about 27 segments. Caudal region with at least 20 poorly-defined ankylosed segments.|