Prídolí graptolites from the Iberian Peninsula: a review of previous data and new records

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Prídolí graptolites are relatively rare in Iberia and, in fact, in much of southwestern Europe, because Prídolí to Early Devonian rocks are largely represented by shallow-water sandstones or siltstone-sandstone alternations. The first unambiguous find of Prídolí graptolites was the 1979 recovery of Colonograptus? transgrediens from limestone nodules occurring within the lower part of the "Upper Graptolite Shales'' in the Ossa Morena Zone of the Hesperian Massif, Spain. Recent detailed studies of the immediately underlying "Scyphocrinites Limestone'' unit reveal two levels of graptolites: a lower marly shale band with poorly preserved but large numbers of Pristiograptus dubius (s.l.), Colonograptus? cf. parultimus, and Linograptus sp., and a limestone band near the top of the unit yielding specimens of C.? transgrediens preserved in relief. In the Barrancos area of the Ossa Morena Zone of Portugal, a recently sampled 8 m thick section of shales and shales and sandstones has yielded six bands of graptolites, the lowest containing lower or middle Ludlow graptolites, and the three stratigraphically higher collections yielding the lower to middle Prídolí species Linograptus posthumus, Colonograptus? parultimus, C.? parultimus?, Monograptus formosus, and Monograptus bouceki, the last-named species occurring only in the highest collection and suggesting a mid-Prídolí age. The occurrence of Prídolí graptolites (Colonograptus? ultimus) is confirmed in the Sil syncline of the northernmost part of the Central Iberian Zone (northwestern Spain). Outside Iberia, but still within the southwestern European part of the North Gondwanan realm, Prídolí graptolites are known in the Armorican Massif of western France (Normandy and probably central Brittany), in Montagne Noire (southern France), and in southwestern Sardinia (Italy).