Microborings in mollusk shells, Bay of Safaga, Egypt: Morphometry and ichnology

Boring patterns of microbial endoliths were analyzed in bivalve shells collected from different environments in the Northern Bay of Safaga on the Red Sea, Egypt. A total of 20 ichnotaxa have been recognized within 64 samples and evaluated on the basis of 250 scanning electron micrographs. The analysis of microorganisms in shells from the same depth profile has been performed separately. Morphological properties of selected ichnotaxa were studied in detail, morphometric parameters established, measured, and statistically evaluated. This method was applied to determine the variability of dominant traces in view of their ichnotaxonomic treatment. Ichnogenus Rhopalia was discussed and a new ichnospecies Rhopalia spinosa was described. Formal change of name for cyanobacterial traces of Hyella and Solentia from Fasciculus to Fascichnus, and for the traces of the green alga Ostreobium from Reticulina to Ichnoreticulina were proposed on the ground of the priority rights in compliance with rules of the International Code of Zoological Nomenclature.