Enigmatic traces in infaunal bivalves from the late Quaternary of Argentina, Southwestern Atlantic. Bioerosion, bioclaustration or nothing?
| Autor: | Ester A. Farinati, Marina Laura Aguirre, Lucía E. Gómez-Peral, Sebastián Miguel Richiano, Ignacio Castellanos, Karen Davies |
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| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
010506 paleontology
Pleistocene Biotic interactions Intertidal zone 010502 geochemistry & geophysics Geociencias multidisciplinaria 01 natural sciences SOUTHWESTERN ATLANTIC Ciencias de la Tierra y relacionadas con el Medio Ambiente purl.org/becyt/ford/1 [https] Paleontology purl.org/becyt/ford/1.5 [https] Geología Southwestern Atlantic 0105 earth and related environmental sciences Abiotic component Bioclaustration LATE QUATERNARY Tagelus plebeius Bioerosion Bivalve BIOCLAUSTRATION BIOTIC INTERACTIONS Space and Planetary Science Regular pattern BIVALVE Quaternary Late quaternary Geology CIENCIAS NATURALES Y EXACTAS |
| Zdroj: | CONICET Digital (CONICET) Consejo Nacional de Investigaciones Científicas y Técnicas instacron:CONICET |
| Popis: | Ichnological investigations were carried out on late Quaternary shells of the intertidal deep infaunal bivalve Tagelus plebeius (Lightfoot, 1786) found along the southwestern Atlantic, between Uruguay and the southernmost Buenos Aires Province in Argentina. Analyses reveal distinctive marks that are spread on the outer shell surface only. The marks are regular-unbranched-elongate, perpendicular to the outer shell growth lines, with deflections on the margins, never interconnected, without bifurcations, conforming bottom-up constructions. They occur in hundreds of specimens from many samples taken from sediments ranging in age from the late Pleistocene to the Recent. These marks have never been reported or described for this species and their origin and formation remain elusive. We describe these traces thoroughly and we propose an explanation for their preservation on about half the shells examined. Potential destructive boring structures (excavated from outside-in) or bioerosion activities by other macro- or micro-organisms are dismissed. These antimarginal asymmetric traces point instead to a process of constructive bioclaustrations (grown from the bottom-up) produced in situ during the life of the bivalve by unknown symbiont organisms. Additionally, the regular pattern observed for the marks exclude host growth as a consequence of abiotic/extrinsic causes. From a palaeoecological perspective, these structures suggest a biotic interaction that was hitherto undescribed neither for bivalves nor for the late Quaternary of the southwestern Atlantic. Facultad de Ciencias Naturales y Museo Centro de Investigaciones Geológicas |
| Databáze: | OpenAIRE |
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