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| Sánchez,Teresa M.. |
| En los últimos años se publicaron numerosas contribuciones sobre procesos heterocrónicos pero son escasos los análisis de los cambios en la forma (espaciales) o heterotópicos. La especie Natasia boliviensis (Babin y Branisa, 1987), del Ordovícico Temprano del noroeste argentino, está representada por abundantes ejemplares en distintas etapas de desarrollo que incluyen individuos juveniles con dentición de tipo taxodonte hasta individuos adultos con dentición actinodonte. El desarrollo ontogenético de la dentición en esta especie se interpreta tentativamente como un caso de heterotopía a partir de un antecesor praenuculido desconocido. Los cambios producidos en el contorno de las valvas, en cambio, pueden ser atribuidos a un proceso heterocrónico. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Heterotopía; Tironuculidos; Ordovícico Temprano. |
| Ano: 2009 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0002-70142009000200002 |
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| Sánchez,Teresa M.; Babin,Claude. |
| Bivalves from the Sella Formation (middle Arenig, Tarija, Bolivia) are described and illustrated. The taxa recognized are Hemiprionodonta lusitanica (Sharpe), known from southern Europe (Spain, Armorican Massif, Montagne Noire), Redonia riojana Sánchez from the west-Argentina Famatina basin, and the new species Coxiconchia sellaensis . These species support the paleobiogeographic affinities between the south European (Armorica), Bolivian and west Argentine basins and corroborate the development of an extensive and continuous shelf throughout the northwest margin of Gondwana during the Arenig. Additionally, specimens at different stages of dental development of Natasia boliviensis (Babin and Branisa) are reported. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bivalves; Arenig; Bolivia. |
| Ano: 2005 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0002-70142005000300004 |
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| Sánchez,Teresa M.. |
| On the basis of collections from Tremadoc and Arenig successions of northwestern Argentina, the affinities of Goniophorina Isberg, 1934, are reassessed. Studied material includes ucumariids, lipanellids, Goniophorina , and other specimens for which the new genus Lossella is proposed with the new species L . juancruzi sp. nov. as type species. Goniophorina and Lossella are grouped in the new family Goniophorinidae. Synapomorphies of goniophorinids, ucumariids, and lipanellids lead to the conclusion that Goniophorina integrates a major group of edentulous bivalves, a lineage of which -the ucumariidsprobably gave rise to Anomalodesmata. This fauna represents a rapid, local diversification event that is part of the west-Gondwanan bivalve radiation during the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Goniophorinids; Early Ordovician; Northwestern Argentina. |
| Ano: 2006 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0002-70142006000100009 |
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