The histological structure of the calcified lung of the fossil coelacanth Axelrodichthys araripensis (Actinistia: Mawsoniidae)
| Autor: | François J. Meunier, Gaël Clément, Paulo M. Brito, Didier Geffard-Kuriyama |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
0106 biological sciences
010506 paleontology biology Aptian Latimeria Paleontology Actinistia Axelrodichthys Anatomy biology.organism_classification 010603 evolutionary biology 01 natural sciences 6. Clean water Cretaceous Pulmonary respiration stomatognathic system Mawsoniidae Coelacanth Ecology Evolution Behavior and Systematics 0105 earth and related environmental sciences |
| Zdroj: | Palaeontology. 53:1281-1290 |
| ISSN: | 0031-0239 |
| DOI: | 10.1111/j.1475-4983.2010.01015.x |
| Popis: | The palaeohistological study of the calcified internal organ of Axelrodichthys araripensis Maisey, 1986, a coelacanthiform from the Lower Cretaceous of Brazil (Crato (Aptian) and Santana (Albian) formations of the Araripe Basin), shows that the walls of this organ consist of osseous blades of variable thickness separated from each other by the matrix. This indicates that, in the living individuals, the walls were reinforced by ossified plates, probably separated by conjunctive tissue. This calcified sheath present in Axelrodichthys, as well as in other fossil coelacanths, lies in ventral position relative to the gut and its single anterior opening is located under the opercle, suggesting a direct connection with the pharynx or the oesophagus. The calcified organ of Axelrodichthys, like that of other fossil coelacanths, is here regarded as an ‘ossified lung’ and compared with the ‘fatty lung’ of the extant coelacanth Latimeria. The reinforcement of the pulmonary walls by the overlying osseous blades could be interpreted as a means of adapting volumetric changes in the manner of bellows, a necessary function for ventilation in pulmonary respiration. Other functional hypotheses such as hydrostatic and/or acoustic functions are also discussed. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text