Early Devonian (Late Emsian) shark fin remains (Chondrichthyes) from the Paraná Basin, southern Brazil



Título del documento: Early Devonian (Late Emsian) shark fin remains (Chondrichthyes) from the Paraná Basin, southern Brazil
Revista: Anais da Academia Brasileira de Ciencias
Base de datos: PERIÓDICA
Número de sistema: 000418012
ISSN: 0001-3765
Autors: 1
2
3
Institucions: 1Natural History Museum, Department of Earth Sciences, Londres. Reino Unido
2Universidade Estadual de Ponta Grossa, Departamento de Geociencias, Ponta Grossa, Parana. Brasil
3Universidade do Vale do Rio dos Sinos, Programa de Pos-Graduacao em Geologia, Sao Leopoldo, Rio Grande do Sul. Brasil
Any:
Període: Mar
Volum: 89
Número: 1
Paginació: 103-118
País: Brasil
Idioma: Inglés
Tipo de documento: Artículo
Enfoque: Experimental, aplicado
Resumen en inglés We report on the pioneering discovery of Devonian fish remains in the Paraná Basin, which represents the southernmost record of fishes from that period in mainland South America. The material comes from an outcrop at the lower portion of the São Domingos Formation, within Sequence C of the Paraná-Apucarana sub-basin in Tibagi, State of Paraná. Marine invertebrates are abundant in the same strata. The dark colored fish remains were collected in situ and represent natural moulds of partially articulated shark fin rays (radials). No elements such as teeth or prismatic cartilage have been preserved with the fins rays. This can be attributed to the dissolution of calcium-phosphatic minerals at the early stages of fossilization due to diagenetic processes possibly linked to strong negative taphonomic bias. This may have contributed to the fact that fishes remained elusive in the Devonian strata of this basin, despite substantial geological work done in the Paraná State in recent decades. In addition, the scarcity of fish fossils may be explained by the fact that the Devonian rock deposits in this basin originated in a vertebrate impoverished, cold marine environment of the Malvinokaffric Realm, as previously suspected
Disciplines Biología
Paraules clau: Paleontología,
Peces,
Fósiles,
Tiburones,
Tafonomía,
Devónico,
Chondrichthyes,
Brasil
Keyword: Paleontology,
Fish,
Fossils,
Sharks,
Taphonomy,
Devonian,
Chondrichthyes,
Brazil
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