Johan Lindgren
Senior lecturer
Preservation and Taphonomy of Fossil Insects from the Earliest Eocene of Denmark
Author
Summary, in English
Marine sediments of the lowermost Eocene Stolleklint Clay and Fur Formation of north-western Denmark have yielded abundant well-preserved insects. However, despite a long history of research, in-depth information pertaining to preservational modes and taphonomic pathways of these exceptional animal fossils remains scarce. In this paper, we use a combination of scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX), transmission electron microscopy (TEM) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) to assess the ultrastructural and molecular composition of three insect fossils: a wasp (Hymenoptera), a damselfly (Odonata) and a pair of beetle elytra (Coleoptera). Our analyses show that all specimens are preserved as organic remnants that originate from the exoskeleton, with the elytra displaying a greater level of morphological fidelity than the other fossils. TEM analysis of the elytra revealed minute features, including a multilayered epicuticle comparable to those nanostructures that generate metallic colors in modern insects. Additionally, ToF-SIMS analyses provided spectral evidence for chemical residues of the pigment eumelanin as part of the cuticular remains. To the best of our knowledge, this is the first occasion where both structural colors and chemical traces of an endogenous pigment have been documented in a single fossil specimen. Overall, our results provide novel insights into the nature of insect body fossils and additionally shed light on exceptionally preserved terrestrial insect faunas found in marine paleoenvironments.
Department/s
- Lithosphere and Biosphere Science
Publishing year
2022-03-03
Language
English
Publication/Series
Biology
Volume
11
Issue
3
Document type
Journal article
Publisher
MDPI AG
Topic
- Geology
Keywords
- cuticle
- Eocene
- Fur Formation
- insects
- melanin
- mo-clay
- pigment
- Stolleklint Clay
- structural coloration
- Ølst Formation
Status
Published
Project
- Exceptional fossil preservation: implications for palaeobiology and taphonomy
ISBN/ISSN/Other
- ISSN: 2079-7737