Lichen Bioerosion on Fossil Vertebrates from the Cenozoic

ACOSTA HOSPITALECHE, C .; MARQUEZ, G.; PEREZ, L.; ROSATO, V.; CIONE

ICHNOS-AN INTERNATIONAL JOURNAL FOR PLANT AND ANIMAL TRACES

TAYLOR & FRANCIS INC

Lugar: Londres; Año: 2011 vol. 18 p. 1 - 8

1042-0940

Different traces occur on fossil bones and teeth coming fromthe Early Miocene Gaiman Formation (Patagonia, Argentina).Most traces were attributed to the action of terrestrial and marinepredators and scavengers. However, other traces on bones andteeth from this unit and one tooth from the Eocene La MesetaFormation (Antarctica) are attributed to chemical corrosion bylichens in recent times, that is, in a very late diagenetic time. Theliving lichens and calcium oxalate deposits occurring on the tracesand their particular pattern indicates that they were not producedby vegetal roots. The lichens include reproductive structures whichallowed a proper determination. A kind of corrosion pattern(Type 1) on bones and teeth from Patagonia is associated toSarcogyne orbicularis K¨ orber, Verrucaria sp. Schrad, and Buelliaaff. punctiformis (Hoff.) Massal. The lichen Aspicilia aff. aquaticaproduced rounded holes on an Antarctic tooth (Type 2). On thesame tooth, the epilithic lichen Caloplaca sp. Th. Fries did notleave any kind of mark on the enameloid.