An Early Cretaceous astropectinid (Echinodermata, Asteroidea) from Patagonia (Argentina): A new species and the oldest record of the family for the Southern Hemisphere

Asterozoans are free living, star-shaped echinoderms which are important components of benthic marine faunas worldwide. Their fossil record is, however, poor and fragmentary, probably due to dissarticulation of ossicles. In particular, fossil asteroids are infrequent in South America. A new species...

Descripción completa

Guardado en:
Detalles Bibliográficos
Publicado: 2014
Materias:
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_07187092_v41_n1_p210_Fernandez
http://hdl.handle.net/20.500.12110/paper_07187092_v41_n1_p210_Fernandez
Aporte de:
id paper:paper_07187092_v41_n1_p210_Fernandez
record_format dspace
spelling paper:paper_07187092_v41_n1_p210_Fernandez2023-06-08T15:43:16Z An Early Cretaceous astropectinid (Echinodermata, Asteroidea) from Patagonia (Argentina): A new species and the oldest record of the family for the Southern Hemisphere Astropectinidae Early cretaceous Mulichinco formation Neuquén basin Patagonia Tethyaster Cretaceous echinoderm fossil record morphology new species Southern Hemisphere taxonomy Argentina Neuquen Basin Patagonia Asteroidea Asterozoa Astropectinidae Echinodermata Tethyaster Asterozoans are free living, star-shaped echinoderms which are important components of benthic marine faunas worldwide. Their fossil record is, however, poor and fragmentary, probably due to dissarticulation of ossicles. In particular, fossil asteroids are infrequent in South America. A new species of starfish is reported from the early Valanginian of the Mulichinco Formation, Neuquén Basin, in the context of a shallow-water, storm-dominated shoreface environment. The specimen belongs to the Astropectinidae, and was assigned to a new species within the genus Tethyaster Sladen, T. antares sp. nov., characterized by a R:r ratio of 2.43:1, rectangular marginals wider in the interbrachial angles, inferomarginals (28 pairs along a median arc) with slightly convex profile and flat spines (one per ossicle in the interbrachials and two per ossicle in the arms). Both the sedimentologic features of the bearing bed, and the taphonomic signature point to a rapid burial. Considering the presence of well-developed fascioles, it is likely that the specimen was already half buried at the beginning of its taphonomic pathway. This record represents the oldest finding of Astropectinidae in the Southern Hemisphere and the first record of the genus Tethyaster for the Lower Cretaceous of South America. 2014 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_07187092_v41_n1_p210_Fernandez http://hdl.handle.net/20.500.12110/paper_07187092_v41_n1_p210_Fernandez
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Astropectinidae
Early cretaceous
Mulichinco formation
Neuquén basin
Patagonia
Tethyaster
Cretaceous
echinoderm
fossil record
morphology
new species
Southern Hemisphere
taxonomy
Argentina
Neuquen Basin
Patagonia
Asteroidea
Asterozoa
Astropectinidae
Echinodermata
Tethyaster
spellingShingle Astropectinidae
Early cretaceous
Mulichinco formation
Neuquén basin
Patagonia
Tethyaster
Cretaceous
echinoderm
fossil record
morphology
new species
Southern Hemisphere
taxonomy
Argentina
Neuquen Basin
Patagonia
Asteroidea
Asterozoa
Astropectinidae
Echinodermata
Tethyaster
An Early Cretaceous astropectinid (Echinodermata, Asteroidea) from Patagonia (Argentina): A new species and the oldest record of the family for the Southern Hemisphere
topic_facet Astropectinidae
Early cretaceous
Mulichinco formation
Neuquén basin
Patagonia
Tethyaster
Cretaceous
echinoderm
fossil record
morphology
new species
Southern Hemisphere
taxonomy
Argentina
Neuquen Basin
Patagonia
Asteroidea
Asterozoa
Astropectinidae
Echinodermata
Tethyaster
description Asterozoans are free living, star-shaped echinoderms which are important components of benthic marine faunas worldwide. Their fossil record is, however, poor and fragmentary, probably due to dissarticulation of ossicles. In particular, fossil asteroids are infrequent in South America. A new species of starfish is reported from the early Valanginian of the Mulichinco Formation, Neuquén Basin, in the context of a shallow-water, storm-dominated shoreface environment. The specimen belongs to the Astropectinidae, and was assigned to a new species within the genus Tethyaster Sladen, T. antares sp. nov., characterized by a R:r ratio of 2.43:1, rectangular marginals wider in the interbrachial angles, inferomarginals (28 pairs along a median arc) with slightly convex profile and flat spines (one per ossicle in the interbrachials and two per ossicle in the arms). Both the sedimentologic features of the bearing bed, and the taphonomic signature point to a rapid burial. Considering the presence of well-developed fascioles, it is likely that the specimen was already half buried at the beginning of its taphonomic pathway. This record represents the oldest finding of Astropectinidae in the Southern Hemisphere and the first record of the genus Tethyaster for the Lower Cretaceous of South America.
title An Early Cretaceous astropectinid (Echinodermata, Asteroidea) from Patagonia (Argentina): A new species and the oldest record of the family for the Southern Hemisphere
title_short An Early Cretaceous astropectinid (Echinodermata, Asteroidea) from Patagonia (Argentina): A new species and the oldest record of the family for the Southern Hemisphere
title_full An Early Cretaceous astropectinid (Echinodermata, Asteroidea) from Patagonia (Argentina): A new species and the oldest record of the family for the Southern Hemisphere
title_fullStr An Early Cretaceous astropectinid (Echinodermata, Asteroidea) from Patagonia (Argentina): A new species and the oldest record of the family for the Southern Hemisphere
title_full_unstemmed An Early Cretaceous astropectinid (Echinodermata, Asteroidea) from Patagonia (Argentina): A new species and the oldest record of the family for the Southern Hemisphere
title_sort early cretaceous astropectinid (echinodermata, asteroidea) from patagonia (argentina): a new species and the oldest record of the family for the southern hemisphere
publishDate 2014
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_07187092_v41_n1_p210_Fernandez
http://hdl.handle.net/20.500.12110/paper_07187092_v41_n1_p210_Fernandez
_version_ 1768541757492953088