Cratonaia novaolindensis gen. et sp. nov. (Unionida, Silesunionoidea) from the Aptian of Brazil (Araripe Basin), and its implications for the early evolution of freshwater mussels

Author(s)

da Silva, Victor R. ^[1] ; Varejao, Filipe G. ^[1] ; Matos, Suzana A. ^[2] ; Fuersich, Franz T. ^[3] ; Skawina, Aleksandra ^[4] ; Schneider, Simon ^[5] ; Warren, Lucas V. ^[1] ; Assine, Mario L. ^[1] ; Simoes, Marcello G. ^[2]

Affiliation

^[1] Univ Estadual Paulista UNESP, Dept Geol Aplicada, Inst Geociencias & Ciencias Exatas, Ave 24-A, BR-13506900 Rio Claro, SP - Brazil

^[2] Univ Estadual Paulista UNESP, Inst Biociencias, Dept Zool, Dist Rubiao Jr S-n, BR-18618970 Botucatu, SP - Brazil

^[3] Friedrich Alexander Univ Erlangen Nurnberg, FG Palaoumwelt, GeoZentrum Nordbayern, Loewenichstr 28, D-91054 Erlangen - Germany

^[4] Univ Warsaw, Fac Biol, Dept Anim Physiol, Ilii Miecznikowa 1, PL-02096 Warsaw - Poland

^[5] CASP, West Bldg, Madingley Rd, Cambridge CB3 0UD - England

• Document type: Journal article
• Source: CRETACEOUS RESEARCH; v. 107, MAR 2020.
• Web of Science Citations: 0

Abstract

The fossil-rich carbonate deposits of the Aptian Crato Formation, Araripe Basin (Brazil) are one of the main Cretaceous Konservat-Lagerstatten of Gondwana, and have come to fame globally. However, information on fossils from deposits other than the famous laminites of the basal part of the unit is scarce. Herein, we describe the first bivalves of the suborder Silesunionidina Skawina and Dzik, 2011 in the order Unionida Gray, 1854 from South America. The specimens were collected from a 0.3-1-m-thick grey to yellow mudstone interval located 0.3 m above the laminated limestones of the lower part of the Crato Formation at Nova Olinda, State of Ceara. They comprise exquisite composite, internal and external moulds, preserving key anatomical characters. Based on the analysis of muscle scars, hinge and ornamentation, these bivalves are here assigned to a new genus and species, Cratonaia novaolindensis gen. et sp. nov. The presence of a series of small pedal elevator scars linearly arranged on the external wall of the umbonal cavity indicates that this is a member of the suborder Silesunionidina. The new form is the by far youngest representative of this group. Closely related bivalves were previously reported from Triassic deposits of Australia, Africa, Europe and potentially India. Detailed stratigraphic, sedimentological and taphonomic observations indicate that the new taxon thrived in a freshwater lake. The occurrence of Silesunionoidea in the Lower Cretaceous of South America indicates that the condition of the musculature in Mesozoic freshwater mussels needs to be established to assign them confidently at family level. (C) 2019 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 14/00519-9 - Centralities of night-time leisure in the city of São Carlos-SP and the interface relations
• Grantee: Tiago Ferreira Lopes Machado
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 16/13214-7 - Multi-proxy approach of the mixed carbonate-siliciclast Crato Formation: sedimentary evolution, paleogeography and tectonics
• Grantee: Filipe Giovanini Varejão
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 17/20803-1 - Stratigraphic and Paleoenvironmental Context of the Macroinvertebrate Assemblages of the Romualdo Formation, Cretaceous, Araripe Basin, and its Paleogeographic Implications
• Grantee: Suzana Aparecida Matos da Silva
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 17/22036-8 - Systematics and paleoecology of the bivalves of the crato formation (Lower Cretaceous), Northeastern Brazil: paleoenvironmental and paleogeographic significance
• Grantee: Victor Ribeiro da Silva
• Support Opportunities: Scholarships in Brazil - Master