Caught in the act? Distraction sinking in ammonoid cephalopods

  title={Caught in the act? Distraction sinking in ammonoid cephalopods},
  author={Royal H. Mapes and Neil H. Landman and Christian Klug},
  journal={Swiss Journal of Palaeontology},
Two specimens of the Late Mississippian ammonoid cephalopod Metadimorphoceras sp. were recovered from the Bear Gulch Limestone in Montana. This unit was deposited in the lowest part of the Big Snowy Basin, where the bottom waters are thought to have been strongly oxygen deficient. The two nearly equally sized specimens are impressions with soft tissues preserved as brown carbonaceous smears. Diagenetic processes destroyed their aragonitic shells. The preserved soft tissues are interpreted as… 

First record of non-mineralized cephalopod jaws and arm hooks from the latest Cretaceous of Eurytania, Greece

The fossils described here document the presence of a typical Mesozoic cephalopod assemblage until the end of the Cretaceous in the eastern Tethys and document the first belemnoid arm hooks from the Tethyan Maastrichtian.

Failed prey or peculiar necrolysis? Isolated ammonite soft body from the Late Jurassic of Eichstätt (Germany) with complete digestive tract and male reproductive organs

The reproductive organs show traces of what might have been spermatophores, thus supporting the hypothesis that the microconchs represented the males, and the soft parts were separated from the conch either taphonomically (following necrolytical processes affecting the attachment structures) or during a failed predation.

The polyphasic ontogeny of the discoidal Late Devonian ammonoid Acrimeroceras

Quantification of ontogenetic change in the two species demonstrates that the stratigraphically younger species A. falcisulcatum possesses the less complex ontogeny compared to the stratigenically older A. stella.

Preservation of nautilid soft parts inside and outside the conch interpreted as central nervous system, eyes, and renal concrements from the Lebanese Cenomanian

Two specimens of Syrionautilus libanoticus (Cymatoceratidae, Nautilida, Cephalopoda) from the Cenomanian of Hadjoula are described and fossilised structures are homologised as remains of the digestive tract, the central nervous system, the eyes, and the mantle.

Ammonoid soft tissue remains revealed by computed tomography

Findings of ammonoid soft tissues are extremely rare compared to the rich fossil record of ammonoid conchs ranging from the Late Devonian to the Cretaceous/Paleogene boundary. Here, we apply the

Life and death in the Jurassic seas of Dorset, Southern England

<p>There are very few examples of predatory behaviour by coleoids in the fossil record (e.g., Jenny <em>et al</em>., 2019) and, in the known cases, the victims are always fish. The examples

The representation of animal behaviour in the fossil record

Special issue: Cephalopods through time

In March and April 2018, the 10th International Symposium Cephalopods—Present and Past (ISCPP) was held in Fes, Morocco. Meeting and the post-conference fieldtrip were organized by representatives of

Distraction sinking and fossilized coleoid predatory behaviour from the German Early Jurassic

A fossil of a co-occurrence of representatives of two different octobrachian coleoid species from the Toarcian Posidonienschiefer of Ohmden near Holzmaden supports the idea that primitive vampyromorphs pursued diverse feeding strategies and were not yet adapted to being opportunistic feeders in oxygen minimum zones like their modern relative Vampyroteuthis.



Upper Paleozoic cephalopod mandibles: frequency of occurrence, modes of preservation, and paleoecological implications

  • R. Mapes
  • Environmental Science, Geography
    Journal of Paleontology
  • 1987
Thirty localities in the Upper Paleozoic (Mississippian–Permian) of North America have yielded more than 1,000 cephalopod mandibles preserved as carbon films, pyrite/limonite internal molds, and as

Soft–part preservation in heteromorph ammonites from the Cenomanian–Turonian Boundary Event (OAE 2) in north–west Germany

Abstract:  From thinly laminated marlstones of the Hesseltal Formation, representing the Late Cenomanian Oceanic Anoxic Event (OAE) 2, at Lengerich in the Teutoburger Wald (Westfalen, north‐west

Origin of the Bear Gulch Beds (Namurian, Montana, USA)

The oldest Gondwanan cephalopod mandibles (Hangenberg Black Shale, Late Devonian) and the mid‐Palaeozoic rise of jaws

It is widely accepted that the effects of global sea‐level changes at the transition from the Devonian to the Carboniferous are recorded in deposits on the shelf of northern Gondwana. These latest

Mature Modifications and Sexual Dimorphism

Most ammonoids display a distinctly different morphology when they are adults or subadults. Depending on the taxon, these mature modifications may comprise changes in coiling, changes in

Caught in the act: the first record of copulating fossil vertebrates

It is reported that from the Eocene Messel Pit Fossil Site between Darmstadt and Frankfurt, Germany numerous pairs of the fossil carettochelyid turtle Allaeochelys crassesculpta represent for the first time among fossil vertebrates couples that perished during copulation.

Ammonoid Paleobiology: From anatomy to ecology

Topics in Geobiology series treats geobiology – the broad discipline that covers the history of life on Earth. The series aims for high quality, scholarly volumes of original research as well as

Ecology, Distribution, and Population Characteristics of Nautilus

Until recently, knowledge of the ecology of Nautilus was largely based on trapping results, observations of captured animals held in shallow water, and speculation and hearsay. Despite the

Preliminary report on the age and palynology of the Bear Gulch Limestone (Mississippian, Montana)

  • Robt S. Cox
  • Geology, Environmental Science
    Journal of Paleontology
  • 1986
Palynostratigraphic study of the Bear Gulch Member of the Heath Formation, central Montana, indicates an Upper Mississippian age for the deposit corresponding to Carboniferous palynofloral zone TK