Morphology and environment in the Jurassic Nucleatidae (Brachiopoda) from Western Tethys

摘要: Nucleatidae (Brachiopoda, Terebratulida) are commonly considered as typical members of the Mediterranean assemblages during Jurassic. However, nucleatids occasionally also occur in margins Western Tethys (Northwestern European shelf). Some these occurrences northeastern Spain analysed, detecting a relation between nucleatid morphology and palaeoenvironment The validity this relationship for whole representatives group Jurassic is tested by means morphofunctional analyses (principal components analysis discriminant analysis), concluding that reduction lateral expansion shell key morphological feature whereby epioceanic epicontinental taxa differ. This change can have functional significance because it be interpreted mechanism to reduce area exposed when valves gape, increasing protection against harmful particles environments characterized higher terrigenous input. modifications on systematics at genus level proposed basis temporal biogeographical distribution adaptations.