title: Cenomanian−Turonian (Upper Cretaceous) gastropods from the Sergipe Basin, north-eastern Brazil
creator: Lexen, Manuela
subject: 560
subject: 560 Paleontology Paleozoology
description: Forty-seven taxa of gastropods are described from the Cenomanian–Turonian (Upper Cretaceous) of the Sergipe Basin in north-eastern Brazil. Because of the generally poor preservation as moulds lacking diagnostic characters, the majority of the taxa are left in open nomenclature. The fauna is dominated by Caenogastropoda (83 %), with subordinate Heterobranchia (14 %) and Vetigastropoda (3 %) and comprises the cosmopolitan genera Turbo (Turbinidae); Pseudamaura (Pseudamaurinidae); Mesalia and Turritella (Turritellidae); “Cerithium” (Cerithiidae); Gyrodes and Euspira (Naticidae); Aporrhais, Drepanocheilus, Piestochilus and Anchura (Aporrhaidae); Tylostoma (Tylostomatidae); Acirsa and Epitonium (Epitoniidae); Fasciolaria (Fasciolariidae); Trophon (Muricidae); Volutilithes and Volutomorpha (Volutodermidae); Pyropsis (Pyropsidae); Nerinea (Nerineidae); Avellana (Ringiculidae); Bulla (Bullidae) and Cylichna (Bullomorpha). The taxa are similar to those of the Tethys, the Western Interior Seaway and the North and South Atlantic. On the basis of representatives of the genera Gyrodes, Piestochilus and Pseudamaura, an upper Turonian assemblage zone, the Piestochilus? (Cryptorhytis?) bleicheri Zone, is established. The presence of endobenthic filtering genera indicates soft substrate in shallow waters with high nutrient levels in near-bottom waters. The oceanic anoxic event 2 (OAE 2) at the Cenomanian−Turonian boundary apparently did not influence the gastropod fauna. Three-dimensional (3D) data enable the generation of high-resolution visualizations based on mathematical algorithms. In addition to the advantage of digital preservation, surface details are made visible and accentuated without damaging the original specimens, and the recognition of characters and shell morphology as well as illustration of the specimens are facilitated.
date: 2013
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/15736/1/Dissertation_Lexen.pdf
identifier: DOI:10.11588/heidok.00015736
identifier: urn:nbn:de:bsz:16-heidok-157360
identifier:   Lexen, Manuela  (2013) Cenomanian−Turonian (Upper Cretaceous) gastropods from the Sergipe Basin, north-eastern Brazil.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/15736/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng