Palaeobiogeographical relationships of poriferan and coral assemblages during the late Carboniferous and the closure of the western Palaeotethys Sea-Panthalassan Ocean connection

Palaeobiogeographical correlations based on poriferan and cnidarian taxa are proposed between the Iberian Peninsula and other basins for the Pennsylvanian, especially the North American Midcontinent. The available data indicate that poriferan and cnidarian diversity in the Iberian Peninsula was highest during the upper Carboniferous, and particularly during the Moscovian. A comparison using Dice's Coefficient shows a great similarity between the Iberian and North American fossil assemblages during this time, suggesting that the marine connection between the Palaeotethys Sea and the Panthalassan Ocean stayed open through the Moscovian, delaying the complete collision of Euramerica and Gondwana until the Kasimovian.