Spinicaudatans from the Upper Jurassic of Argentina and their paleoenvironments

Spinicaudatans are a diverse and geographically widespread group of small branchiopod crustaceans with an excellent fossil record. They inhabit ephemeral freshwater habitats with warm conditions and pH levels from neutral to alkaline. Many studies have been performed on the systematics of this group...

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Detalles Bibliográficos
Autores: Monferran, Mateo Daniel, Cabaleri, Nora Graciela, Gallego, Oscar Florencio, Armella, Claudia, Cagnoni, Mariana Celina
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2016
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/30438
Acceso en línea:http://hdl.handle.net/11336/30438
Access Level:acceso abierto
Palabra clave:Spinicaudatans
Continental Palaeoenvironments
Upper Jurassic
Cañadon Asfalto Basin
Argentina
https://purl.org/becyt/ford/1.5
https://purl.org/becyt/ford/1
Descripción
Sumario:Spinicaudatans are a diverse and geographically widespread group of small branchiopod crustaceans with an excellent fossil record. They inhabit ephemeral freshwater habitats with warm conditions and pH levels from neutral to alkaline. Many studies have been performed on the systematics of this group, also known as ´conchostracans´, although the paleoecology of these clam shrimp has not been widely analyzed. This paper examines some aspects of the relationship between spinicaudatans and their environments from the Upper Jurassic (Canadon Asfalto Formation) of Argentina. We used sedimentological analysis to infer paleoenvironmental factors. Spinicaudatan features were also measured, including carapace size, growth band width, and growth lines. The results of this study reveal that the observed spinicaudatan species (Congestheriella rauhuti, Wolfestheria smekali, and Wolfestheria sp.) would have lived in carbonate lacustrine systems characterized by benthic microbial communities dominated by cyanobacteria. However, environmental factors such as oxygenation, pyroclastic deposits, and associated fauna (fish, ostracods, bivalves, and charophytes) were different at each locality. The spinicaudatan carapaces also show varying morphological features such as small or large carapace size, narrow or wide growth bands and low or high density of growth lines. These differences are related to abiotic (volcanic-oxygen) and biotic (fish and microbial) factors regarded as important agents for the development of the spinicaudatan populations.