New Eocene Antarctic chimeroid fish (Holocephali, Chimaeriformes)

ABSTRACT: Until now Eocene chimeroid holocephalians of Antarctica have been known from only a few specimens attributed to two species from the Eocene of Seymour Island. New material collected by Polish and English field parties includes numerous tooth plates and fin spine fragments from the Eocene L...

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Bibliographic Details
Main Authors: Jürgen Kriwet, Andrzej Gaździcki
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.608.4596
http://www.polar.pan.pl/ppr24/ppr24-029.pdf
Description
Summary:ABSTRACT: Until now Eocene chimeroid holocephalians of Antarctica have been known from only a few specimens attributed to two species from the Eocene of Seymour Island. New material collected by Polish and English field parties includes numerous tooth plates and fin spine fragments from the Eocene La Meseta Formation. We describe a new species, Callorhinchus stahli, based on two mandibular and a single fragmentary palatine tooth plate. In addition, the stratigraphic distribution and diversity of Eocene Antarctic chime− roids is discussed. The chimeroid Ischyodus shows the greatest stratigraphic distribution with its greatest abundance in the middle parts of the La Meseta Formation while Chimaera and Callorhinchus are restricted to the lower ones. Changes in the environment and habitat availability most probably triggered the distributional pattern and the disappearance of chimeroids. K e y w o r d s: Antarctica, La Meseta Formation (Eocene), palaeontology (chimeroid fish), new species, ecology.