Mise en évidence d'algueraies à Caulerpa par les Juliidae (gastéropodes à 2 valves: Sacoglossa) dans l'Éocène du Bassin de Paris
In: Géobios. Association Européenne de Paléontologie: Lyon. ISSN 0016-6995; e-ISSN 1777-5728, more
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Keywords |
Climate > Palaeoclimate Flora > Weeds > Marine organisms > Seaweeds Geological time > Phanerozoic > Geological time > Cenozoic > Paleogene > Palaeogene > Eocene Palaeo studies > Ecology > Palaeoecology Salinity Caulerpa J.V.Lamouroux, 1809 [WoRMS]; Gastropoda [WoRMS]; Juliidae E. A. Smith, 1885 [WoRMS]; Mollusca [WoRMS] France [Marine Regions]
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Author keywords |
Biological Evolution; Photosynthetic Mutualism; Environmental Indicator; Bathymetric Indicator; Paris Basin |
Abstract |
When studying the biology and ecology of Juliidaeliving representatives (Gastropoda, Opisthobranchia, Sacoglossa) a close relationship can be observed between these animals and green Algae of the genus Caulerpa (Chlorophycea, Siphonophycidae). The animal feeds on the host plant by sucking the sap of the Alga, and moreover seems to use the ingested chloroplasts for a functional photosynthesis. Each species of Juliidae is found living on only one (or sometimes two) species of Caulerpa.The fossil Juliidae prove the existence of Caulerpagrowing at the same places, though these algae do not leave any direct remnant of their presence. Applying this to the Paris Basin Eocene, where the Juliidae are relatively abundant and varied, a quite accurate estimate is given for many characteristics of the paleo-environment, by analogy with the narrow and strict ecological needs of the living representatives (bathymetry, temperature and oxygenation of water, and presence of Caulerpa sea weeds). |
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