Cyclostomi

Cyclostomi
Temporal range: Lochkovian - Recent 419.2–0 Ma
Sea lamprey from Sweden
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Infraphylum: Agnatha
Superclass: Cyclostomi
Duméril, 1806
Classes

Cyclostomi, often referred to as Cyclostomata /sɪklˈstɒmətə/, is a group of vertebrates that comprises the living jawless fishes: the lampreys and hagfishes. Both groups have jawless mouths with horny epidermal structures that function as teeth called ceratodontes, and branchial arches that are internally positioned instead of external as in the related jawed fishes.[1] The name Cyclostomi means "round mouths".[2][3][4] It was named by Joan Crockford-Beattie.[5]

  1. ^ The oldest fish in the world lived 500 million years ago | SBS News
  2. ^ Kuraku, Shigehiro, S. Blair; Ota, Kinya G. & Kuratani, Shigeru (2009b). "Jawless fishes (Cyclostomata)". In S.B. Hedges & S. Kumar (eds.). Timetree of Life. Oxford University Press. pp. 317–319. ISBN 978-0-19-953503-3.
  3. ^ Haeckel (1895). Systematische Phylogenie der Wirbelthiere (Vertebrata). Entwurf einer systematischen Stammesgeschichte (in German). Vol. 3 (1 ed.). Berlin: Georg Reimer. pp. 142–143.
  4. ^ Duméril, A.M. Constant (1806). Zoologie analytique, ou me´thode naturelle de classification des animaux, Rendue plus facile a l'Aide de Tableaux Synoptiques (in French). Paris: Allais.
  5. ^ Turner, Susan; Beattie, Joan (2008). "Joan Crockford-Beattie D.Sc." (PDF). Annals of Bryozoology 2: Aspects of the History of Research on Bryozoans. 2: viii, 442.