Decapod assemblages from the Aptian-Albian transition of the eastern Maestrat Basin (Iberian Chain)

Abstract

Two decapod (Arthropoda: Malacostraca: Decapoda) assemblages from two newly discovered localities near Torreblanca (Castelló, Valencian Country, Spain), situated in the Orpesa Sub-basin of the Maestrat Basin, are described. The first assemblage exhibits a diverse fauna of lobsters, including erymoids, glypheoids and nephropoids representatives of five different genera, some of them reported for the first time in Iberia, as well as brachyuran crabs, primarily palaeocorystoids, including one new species, Paranecrocarcinus xivertensis. It is assigned to the uppermost Aptian of the Benassal Formation. The second assemblage, found in the lower Albian Escucha Formation, showcases an exceptional richness of exquisitely preserved complete remains of a new genus and species of axiidean ghost shrimp, Cretagourretia salasi, along with some palaeocorystoids, also representatives of a new species, Joeranina tausi, within a varied community of invertebrates and plants. This work investigates the paleoenvironment in which these assemblages thrived, and explores their faunal similarities with other decapod assemblages from the nearby Garraf Basin, as well as more distant ones such as the Basque-Cantabrian Basin and the Isle of Wight. An ammonite occurrence, likely belonging to the genus Roberticeras, has been identified in the upper Aptian Benassal Formation. Additionally, the juvenile stage of the ammonite Parengonoceras bassei from the lower Albian Escucha Formation is reported and described for the first time. The study provides valuable insights into reconstructing coastal to marine environments and the associated biota that developed in the Maestrat Basin during the Aptian-Albian transition.