Tolypelepidida is an extinct order of heterostracanvertebrates. These armored jawless fish superficially resemble their relatives, the cyathaspids, though, researchers place the tolypelepids as a sister group to the cyathaspids and the pteraspidids (and both groups' daughter taxa).[1] A recent study by Lundgren and Blom in 2013 implies that the order is paraphyletic, with the type genus, Tolypelepis, being the sister taxon of Cyathaspidiformes.[2] The typical tolypelepid had a carapace formed from dorsal and ventral plates, and a scaly tail.
