Ronald Nalin

Genesis and composition of the Pleistocene Coralligène de plateau of the Cutro Terrace (Calabria, southern Italy)

Abstract: Some mid-Pleistocene carbonate build-ups from the marine terrace of Cutro show theuncommon, biologically-induced change of substrate that is implied in the definition of coralligenede plateau : from coarse, biogenic sediment to the solid framework. The build-ups grew over a basalrhodolithic layer mostly composed of Sporolithon ptychoides which was stabilized and transformedinto a hard substrate by the binding activity and overgrowth of non-geniculate Corallinales (calca-reous red algae). The build-ups are dominated by Titanoderma pustulatum , whose role in biogenicconstruction was previously underestimated, in association with Mesophyllum spp. and locally with Lithophyllum stictaeforme . Intergenicula of Amphiroa cryptarthrodia are common. Key words: coralligenous, bio-construction, hard substrate, rhodoliths, Corallinales, calcareousalgae, Pleistocene. 1. Introduction The term coralligene or coralligenous (acronym = C)is commonly applied to carbonate build-ups currentlydeveloping on Mediterranean hard and soft bottoms,at depths ranging from 20 to 160 m (L

Persististrombus latus (Gmelin) in the upper Pleistocene deposits of the marine terraces of the Crotone peninsula (southern Italy)

Persististrombus latus (GMELIN, 1791) (=Strombus bubonius LAMARCK, 1822), is the most iconic representative of the “Senegalese fauna”, a fossil assemblage of tropical water organisms thought to have colonized the Mediterranean Sea during the last interglacial. As such, P. latus has become an important stratigraphic marker of Marine Isotope Stage (MIS) 5.5, allowing the correlation of raised coastal deposits used in studies of sea level variations and tectonic uplift. P. latus is found in shallow marine sediments of Tyrrhenian age (~124 ka) in several localities of the Italian peninsula. However, despite intensive surveying through the years, the late Pleistocene marine terraces of the Crotone peninsula, which preserve an extensive volume of fossiliferous deposits attributed to MIS 5, have yielded very few specimens of P. latus. This paper reports the finding of several new specimens of P. latus near Isola di Capo Rizzuto, in deposits that had been independently assigned to MIS 5.5, and two specimens from the Capo Colonna terrace, which is thought to correlate with MIS 5.3 or 5.1. The Crotone peninsula, therefore, represents one of the few localities in Italy where multiple stratigraphically distinct P. latus-bearing units can be observed.