Mathesia darderi (Astre) (Bivalvia, Hippuritoidea, Monopleuridae): Morphological, biogeographical and ecological changes in the Mediterranean domain during the late Barremian–Albian

摘要: Abstract Mathesia darderi , a slender cylindrical monopleurid genus, formerly documented from the late Aptian–Albian of Spain, France, Tunisia, Algeria, Egypt and Turkey, has been discovered in upper Barremian lower Aptian Bulgaria Spain. Notwithstanding some morphological changes, Barremian–lower forms those possess same myocardinal organisation microstructural attributes. The inner shell margin right valve displays scalloped, festooned, tubular vermiform microstructures. most prominent evolutionary trait M. is increase body size through time. A statistical analysis distributions show that populations Barremian–early Aptian, early to middle Albian, are significantly different; pattern which biostratigraphic potential. Ecological changes time expressed by displacement communities central/distal part, proximal part carbonate platforms. present locally its major spreading over European Arabo–African margins Mediterranean Tethys during Clansayesian–lower Albian. disappearance species at Middle–Upper Albian boundary, correlates with critical, spatial reduction