Cephalorhyncha is a name that has been used by Nielsen (2001) for the clade (Priapula + Kinorhyncha + Loricifera), but in its original usage it also includes the Nematomorpha (Halanych 2004 and references therein). In the narrow sense of Nielsen (2001), this clade has also been termed the Scalidophora. Based on new molecular data and analyses, Sørensen et al. (2008) concluded that the Loricifera and Nematomorpha appear to be sister taxa, which would make the Cephalorhyncha sensu Nielsen 2001 (or Scalidophora) clade paraphyletic. As of 2010, relationships among phyla within the Ecdysozoa remain poorly resolved, so it is difficult to know which groups will eventually win wide acceptance by specialists as convincingly monophyletic and deserving of a name.
