Late Cretaceous Elopomorpha (Actinopterygii: Teleostei) from the Mahajanga Basin of Madagascar and impacts on paleobiogeography

Palaeontologia Electronica

article

Summer A. Ostrowski¹ 

[1] University of Wisconsin-Parksid

关键词: Gondwana;    Cretaceous;    Madagascar;    Albula;    Egertonia;    Paralbula;    palaeobiogeography;   

DOI  :  10.26879/1151

学科分类：社会科学、人文和艺术（综合）

来源: Palaeontologia Electronica

【 摘 要 】

The Upper Cretaceous deposits of Madagascar have produced a rich terrestrial vertebrate fauna. Studies of Madagascar’s endemic fossils and recent fauna have led to multiple hypotheses surrounding the origin of these clades on the island following its complete isolation 88 m.y.a. This report is the first published description of several representatives of fossil Elopomorpha (Teleostei) from the Late Cretaceous of Madagascar. Elopomorphs are primarily marine fishes and one of the most morphologically diverse groups within teleosts. Fragmentary fossil elopomorph elements often consist of tooth plates and vertebrae. The tooth plates and dentary reported here are diagnostic and identifiable to the generic classification of Albula, Egertonia, and Paralbula. The vertebrae are numerous and morphologically variable, which indicates the abundance and importance of elopomorphs in the coastal environment of Madagascar during the Late Cretaceous. Most Cretaceous elopomorphs are from localities in the Northern Hemisphere. While several species of Cretaceous elopomorphs are also found in the Southern Hemisphere, there are not as many in number or kind. These Madagascar fossils represent the oldest Albula and Paralbula fossils recorded from Gondwana, increasing their known spatial range. The Egertonia material described here represents one of the earliest occurrences of the genus, adding to its record during the Cretaceous of Gondwana. The presence of these fishes supports a more global distribution of these genera during the Late Cretaceous and a higher diversity of Elopomorpha in the Southern Hemisphere during the Mesozoic than previously documented.

【 授权许可】

CC BY|CC BY-NC-SA