Fossil of 2020
Recent nautilids are iconic externally shelled cephalopods and a well-studied group, today being restricted to a few species populating relatively small relict habitats in deeper waters. During the Cretaceous, nautiloids were common and environmentally / palaeobiogeographically much more widespread but were rather bradytelic in their evolutionary patterns, commonly resulting in prolonged stratigraphic ranges. Furthermore, many taxa are characterized by inflated shells that indicate overall low hydrodynamic efficiency. However, in the latest Early Cretaceous, a genus of compressed forms with narrow, partly sharp venters arose, i.e. Angulithes de Montfort, 1808, some representatives of which obtained truly oxycone shells and showed fairly short-lived stratigraphic ranges during the Cenomanian age (ca. 100–94 Ma), associated by increased septal folding and decreased inter-septal distances as well as a more-and-more dorsal position of the siphuncle. The late Cenomanian species Angulithes mermeti (see illustration) represents in most of these aspects a climax form. Based on a detailed description, a taxonomical, autecological, stratigraphical and palaeobiogeographic discussion of this exceptional oxycone nautiloid species that successfully conquered (sub-)tropical shallow-water habitats that are today devoid of nautilids has been provided (see Wilmsen & Nagm 2019). Furthermore, the evolutionary trends in Cenomanian species of Angulithes are evaluated in the light of contemporaneous palaeoenvironmental changes and inferred functional traits.
Wilmsen, M. & Nagm, E. (2019): Palaeobiology and evolutionary context of Angulithes mermeti (Coquand, 1862), a streamlined early Late Cretaceous shallow-water nautiloid. – Acta Palaeontologica Polonica, 64: 831–849; Warszawa. [open access]
Revisions
The first and the second part of the revision of the Cretaceous fauna of Saxony already have been published. Part 3 will follow …
NIEBUHR B. & WILMSEN M. (2014, Eds.): Kreide-Fossilien in Sachsen, Teil 1. – Geologica Saxonica 60(1): 1–254; Dresden.
NIEBUHR B. & WILMSEN M. (2016, Eds.): Kreide-Fossilien in Sachsen, Teil 2. – Geologica Saxonica 62: 1–245; Dresden.
All articles are available in open access here.
New publications 2019
Wilmsen, M. & Nagm, E. (2019): Palaeobiology and evolutionary context of Angulithes mermeti (Coquand, 1862), a streamlined early Late Cretaceous shallow-water nautiloid. – Acta Palaeontologica Polonica, 64: 831–849; Warszawa.
Niebuhr, B. (2019): From animal to plant kingdom: the alleged sponge Siphonia bovista Geinitz from the Cretaceous of Saxony (Germany) in fact represents internal moulds of the cone-like plant fossil Dammarites albens Presl in Sternberg. – Bulletin of Geosciences, 94: 221-234; Prag.Smith, K.T., Schwermann, A.H. & Wilmsen, M. (2019): The oldest articulated mosasaurian remains (earliest Turonian) from Germany. – Geologie und Paläontologie in Westfalen, 91: 3–23; Münster.
Wilmsen, M. & Aly, M.F. (2019): Late Campanian nautiloids from Deir Abu Said, north-western Jordan. – Cretaceous Research, 102: 81–88; Amsterdam.
Lehmann, J., Mosavinia, A. & Wilmsen, M. (2019): Parahoplitid ammonites and narrowing down the Aptian/Albian boundary interval in northern Iran. – Cretaceous Reseach, 94: 207–228; Amsterdam.
Linnert, C., Engelke, J., Wilmsen, M. & Mutterlose, J. (2019): Environmental footprints of the early Maastrichtian cooling – the record of benthic foraminifera from northern Germany. – Cretaceous Research, 97: 143–159; Amsterdam.
Wilmsen, M., Dölling, B., Hiss, M. & Niebuhr, B. (2019): The lower Upper Cretaceous of the south-eastern Münsterland Cretaceous Basin, Germany: facies, integrated stratigraphy and inter-basinal correlation. – Facies, 65: 13 (29pp.); Erlangen.
Wilmsen, M., Engelke, J., Linnert, C., Mutterlose, J. & Niebuhr, B. (2019): A Boreal reference section revisited (Kronsmoor, northern Germany): high-resolution stratigraphic calibration of the Campanian–Maastrichtian boundary interval (Upper Cretaceous). – Newsletters on Stratigraphy, 52: 155–172; Stuttgart.
Wilmsen, M., Niebuhr, B., Fengler, M., Püttmann, T. & Berensmeier, M. (2019): The Late Cretaceous transgression in the Saxonian Cretaceous Basin (Germany): old story, new data and novel findings. – Bulletin of Geosciences, 94: 71–100; Prague.