First pachycormiform (Actinopterygii, Pachycormiformes) remains from the Late Jurassic of the Antarctic Peninsula and remarks on bone alteration by recent bioeroders

GOUIRIC CAVALLI, S.; RASIA, LUCIANO LUIS; MÁRQUEZ, GONZALO; ROSATO, VILMA; SCASSO, ROBERTO A.; REGUERO, MARCELO.

JOURNAL OF VERTEBRATE PALEONTOLOGY

SOC VERTEBRATE PALEONTOLOGY

Lugar: Lawrence; Año: 2019 vol. 38

0272-4634

We describe here osteichthyan remains from the Upper Jurassic of the Ameghino (=Nordenskjöld) Formation of the Antarctic Peninsula. The fish bones are referred to a suspension-feeding pachycormid based on the shape, morphology and presence of acu fanunculi (needle-teeth) on their gill rakers. Due to the fragmentary condition of the Antarctic material, we refer it to aff. Asthenocormus. The fish remains described herein represent the first record of a suspension-feeding pachycormid in the Late Jurassic of the Antarctic Peninsula, being the oldest pachycormid yet recovered from Antarctica. The new fossil fish supports a possible early dispersion route through the Mozambique Corridor or the Trans-Gondwana Seaway. We also describe the weathering produced by modern lichens which might be misinterpreted as original bone structure.