Upper Ovetian trilobites (Cambrian Stage 3) from the Central Iberian Zone (Spain): Systematics and biostratigraphy

Abstract The upper Ovetian (Cambrian Stage 3) trilobites from two localities La Rinconada (Salamanca) and Los Navalucillos (Toledo) — in the Central Iberian Zone have been studied. A review of the geological map and sections at La Rinconada has enabled the precise determination of the stratigraphic position of the trilobite finds. The four trilobite-bearing levels at La Rinconada are located in the upper part of the Tamames Sandstone Formation; five trilobite species were identified, two of which are new: Serrania carlsi and Granolenus rinconadensis . In Los Navalucillos, three levels from the lower part of the Los Navalucillos Formation were studied, yielding four identified species. The presence of Granolenus midi — a species originally described from the Montagne Noire (France) — in both localities enables a correlation between these three regions. Furthermore, the co-occurrence in Los Navalucillos of G. midi with Dolerolenus ( D .) formosus , Metadoxides richterorum , and Lunolenus cf. lunae marks the first record of these species outside their type locality (Los Barrios de Luna, León). This association allows for a precise correlation between the upper Ovetian of the Central Iberian and Cantabrian zones. Additionally, this finding reinforces the previously established correlation between the Cantabrian Zone and Sardinia (Italy). A revised upper Ovetian biozonation is proposed, consisting of the Granolenus rinconadensis , Granolenus midi , and Dolerolenus ( D .) formosus biozones. Finally, the Ovetian biostratigraphic subdivision has been updated based on the trilobite distribution, and the correlation of Ovetian lithostratigraphic units across Spain has been revisited.