Vertebral column and associated elements in dipnoans and comparison with other fishes: Development and homology

  title={Vertebral column and associated elements in dipnoans and comparison with other fishes: Development and homology},
  author={Gloria Arratia and Hans-Peter. Schultze and Jorge Casciotta},
  journal={Journal of Morphology},
A vertebral column consisting of a persistent notochord and ossified arcocentra is the primitive condition for Gnathostomata; it still persists in primitive actinopterygians and sarcopterygians. Advanced actinopterygians and sarcopterygians develop numerous types of centra that include, among others, the presence of holocentrum, chordacentrum, and autocentrum. The chordacentrum, a mineralization or calcification of the fibrous sheath of the notochord, is only found in actinopterygians, whereas… 
Evolution and development of the synarcual in early vertebrates
A survey of placodermsynarcuals shows that taxa such as Materpiscis and Cowralepis are particularly informative because perichondral ossification occurs prior to synarcual fusion such that individual vertebral elements can be identified.
Development of the Synarcual in the Elephant Sharks (Holocephali; Chondrichthyes): Implications for Vertebral Formation and Fusion
The observations on synarcual development in three major groups of early jawed vertebrates indicate that fusion involves heterotopic cartilage and perichondral bone/mineralised cartilage developing outside the regular skeleton.
A Microanatomical and Histological Study of the Postcranial Dermal Skeleton of the Devonian actinopterygian Cheirolepis canadensis
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In Cobitis striata, the basihyal cartilage and anterior copula form as separate cartilages and remain distinct throughout development with a prominent gap between the basithyal and most anterior basibranchial, which the authors interpret as loss of basIBranchial 1.
The caudal skeleton of basal teleosts, its conventions, and some of its major evolutionary novelties in a temporal dimension
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Reevaluation of the caudal skeleton of some actinopterygian fishes: II. Hiodon, Elops, and Albula
The composition of the caudal skeleton of fossil teleosts and the ontogeny of that of Hiodon, Elops, and Albula corroborate a one‐to‐one relationship of ural centra with these dorsal and ventral elements.
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Structure of the vertebral column in Eusthenopteron foordi Whiteaves
X-ray photographs of part of the vertebral column of Eusthenopteron foordi Whiteaves show that each vertebral segment consists of (1) a centrum made up of two thin lateral concentric half rings; (2)
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Lepisosteus and Amia possess a polyural caudal skeleton with a one‐to‐one relationship between ural centra and hypurals; the number of hypural may be reduced in adult Lepisostspecies.
The composition of the caudal skeleton of teleosts (Actinopterygil: Osteichthyes)
This preliminary research demonstrates that a detailed ontogenetic interpretation of the vertebral centra and of the caudal skeleton of different teleosts may be useful tools for further interpretations of teleostean interrelationships.
  • A. Panchen
  • Environmental Science
    Evolution; international journal of organic evolution
  • 1967
The nature of the vertebrae has long been used to define the major taxa within the Labyrinthodontia and to assign a place to the group within the classification of the Amphibia and it is now fairly generally agreed that the rhachitomous vertebra represents the primitive labyrinthodont condition.
The urohyal: Development and homology within osteichthyans
A new structure, the parurohyal, arises as a double ossification of the tendon of the sternohyoideus muscle in siluroids; during ontogeny an anterodorsal crest or cup‐like structure derives from the anterior basibranchial region and the tendon bone; therefore, the arthrohyal is compound in origin.
Reevaluation of the caudal skeleton of certain actinopterygian fishes: III. Salmonidae. Homologization of caudal skeletal structures
The ontogenetic development of caudal vertebrae and associated skeletal elements of salmonids provides information about sequence of ossification and origin of bones that can be considered as a model
Osteology and Phylogenetic Relationships of Fossil and Recent Paddlefishes (Polyodontidae) with Comments on the Interrelationships of Acipenseriformes
ABSTRACT The comparative osteology and phylogenetic relationships of fossil and living paddlefishes (Polyodontidae) are investigated in detail for the first time. This peculiar, poorly known group is
Comparative ultrastructure of the cellular components of the unconstricted notochord in the sturgeon and the lungfish
The cellular ultrastructure of the notochord was examined in the shortnose sturgeon, Acipenser brevirostratus, and in the African lungfish, Protopterus annectens to better understand the function of this organ.