Upper Silurian and Devonian Chitinozoa from central and southern Bolivia, central Andes

A study of chitinozoans from Upper Silurian and Devonian strata from south central Bolivia has provided new stratigraphic information and improved correlations with adjacent basins in Argentina, Paraguay, Uruguay, and Brazil. The investigated succession extends from late Ludlow (upper Kirusillas Formation) to late Frasnian (upper Iquiri Formation). Unconformities in the section or condensed intervals occur in latest Pragian to early Emsian and for most of the Eifelian. Two early Givetian chitinozoan species, Ancyrochitina postdesmea and Ramochitina boliviensis, are newly described.