Microbioerosão em conchas de Heleobia australis (Gastropoda: Rissooidea) da lagoa Salgada,Rio de Janeiro, Brasil.

Abstract

Traces of microbioerosion are recorded on microgastropods shells thatoccur in association with recent stromatolites from lagoa Salgada, Rio de Janeiro State. The high destruction levels produced by microborers on the bioclasts were directly observed through optical and scanning electron microscroscopy. This study goals the identification and description of the bioerosion patterns on microgastropods of the species Heleobia australis (D’Orbigny). Themicroborings consist of sinuous ramified microborings galeries that were related to the ichnogenera Fascichnus, as well as groups of circular and irregular perforations that remained unidentified. Energy Dispersive X-Ray Spectrometry (EDS) analysis of the dark shells surfaces detected the elements sulfur and iron, both closely tied to the microbial metabolism.

Keywords

• microbioerosion
• microgastropods
• EDS
• microbial metabolism
• lagoa Salgada.