Article · Wikipedia archive · Last revised Jun 18, 2026

Cycloneuralia

Cycloneuralia is a proposed clade of ecdysozoan animals including the Scalidophora, the Nematoida, and the extinct palaeoscolecids. It may be paraphyletic, or may be a sister group to Panarthropoda. Or perhaps Panarthropoda is paraphyletic with respect to Cycloneuralia. The group has also been considered a single phylum, sometimes given the old name Nemathelminthes. The uniting character is the nervous system organization with a circumpharyngeal brain and somata–neuropil–somata pattern. The name derives from the position of the brain around the pharynx.

Last revised
Jun 18, 2026
Read time
≈ 1 min
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305 w
Citations
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Source
Wikipedia ↗
Cycloneuralia
Temporal range:
Priapulus caudatus
Scientific classification Edit this classification
Kingdom: Animalia
Subkingdom: Eumetazoa
Clade: ParaHoxozoa
Clade: Bilateria
Clade: Nephrozoa
Clade: Protostomia
Superphylum: Ecdysozoa
(unranked): Cycloneuralia
Subclades

Cycloneuralia is a proposed clade of ecdysozoan animals including the Scalidophora (kinorhynchans, loriciferans, priapulids), the Nematoida (nematodes, nematomorphs), and the extinct palaeoscolecids.12 It may be paraphyletic, or may be a sister group to Panarthropoda. Or perhaps Panarthropoda is paraphyletic with respect to Cycloneuralia.3 The group has also been considered a single phylum, sometimes given the old name Nemathelminthes.4 The uniting character is the nervous system organization with a circumpharyngeal brain and somata–neuropil–somata pattern.5 The name derives from the position of the brain around the pharynx.6

References

References

  1. Schmidt-Rhaesa, A.; Bartolomaeus, T.; Lemburg, C.; Ehlers, U.; Garey, J.R. (1998). "The position of the Arthropoda in the phylogenetic system - Articulata". J. Morphol. 238 (3): 263–285. doi:10.1002/(SICI)1097-4687(199812)238:3<263::AID-JMOR1>3.0.CO;2-L. PMID 29852696. S2CID 46920478. Archived from the original on 10 May 2010.
  2. Telford, MJ; Bourlat, SJ; Economou, A; Papillon, D; Rota-Stabelli, O (April 2008). "The evolution of the Ecdysozoa". Philos. Trans. R. Soc. Lond. B Biol. Sci. 363 (1496): 1529–37. doi:10.1098/rstb.2007.2243. PMC 2614232. PMID 18192181.
  3. Dunn, Casey W.; Hejnol, Andreas; Matus, David Q.; Pang, Kevin; Browne, William E.; Smith, Stephen A.; Seaver, Elaine; Rouse, Greg W.; Obst, Matthias; Edgecombe, Gregory D.; Sørensen, Martin V.; Haddock, Steven H. D.; Schmidt-Rhaesa, Andreas; Okusu, Akiko; Kristensen, Reinhardt Møbjerg; Wheeler, Ward C.; Martindale, Mark Q.; Giribet, Gonzalo (2008). "Broad phylogenomic sampling improves resolution of the animal tree of life". Nature. 452 (7188): 745–749. doi:10.1038/nature06614.
  4. Cavalier-Smith, T. (1998). "A revised six-kingdom system of life" (PDF). Biol. Rev. 73: 203–266. Archived from the original (PDF) on 2016-03-04. Retrieved 2016-02-27.
  5. The neuromuscular system of Pycnophyes kielensis (Kinorhyncha: Allomalorhagida) investigated by confocal laser scanning microscopy - EvoDevo
  6. "Explanations.html". Archived from the original on 2013-02-07. Retrieved 2009-06-28.