Amber- and plant-bearing deposits from the Cenomanian of Neau (Mayenne, France)

Abstract

A new Cenomanian amber- and plant-bearing deposit has been discovered at Neau, in the Mayenne department (France). The Cenomanian fossiliferous lignites are located in karst filling in a substratum of Cambrian limestones. The amber corresponds mainly to tiny millimetric grains, devoid of arthropod inclusions, but rich in microorganisms, especially the sheated bacteria Leptotrichites resinatus, and containing pollen grains (Classopollis) and wood fibers (Araucariacae or Cheirolepidiaceae). The lignites provide abundant conifer and ginkgoale cuticle fragments (Frenelopsis, Eretmophyllum) and a lot of palynomorphs (e.g. Gleicheniidites senonicus, Cyathidites, Deltoidospora, Appendicisporites and Cicatricosisporites). The chemical signature of the amber suggests it was produced by conifers of the extinct family Cheirolepidiaceae. According to the palynological assemblage, the age of the lignites is upper lower Cenomanian or lower mid Cenomanian. The deposit environment corresponded to the upstream portion of a mangrove or the most inner part of a lagoon.

Early Jurassic coprolites: insights into palaeobotany and the feeding behaviour of dinosaurs

“…Its xylology is relatively poorly known (Néraudeau et al . 2020). What is known of it does not contradict the above hypothesis, but neither that nor the observations allow us to exclude the possibility that the specimen of wood is linked to another family of conifers or even to another group of homoxylous plants, such as pteridosperms or Caytoniales.…”

An overview of the Santonian amber-bearing deposits of the Sainte-Baume Massif, southeastern France

“…This Cheirolepidiaceae is often related to the production of amber resins, as it has been argued for the Santonian amber grains of Belcodène (Saint Martin et al, 2013). However, apart the case of exceptional inclusion of identifiable plant debris in amber (Néraudeau et al, 2020), the botanical origin of amber still remains widely debated for each amber deposit, even if the chemical composition of amber grains can give some indications (see Seyfullah et al, 2018 andthe discussion in Valentin et al, 2020). At Piolenc, various leaf cuticle compressions of Corystospermales, Cycadales, Bennettitales, Gymnosperms and mostly Angiosperms are recorded, and testify of a warm and humid, tropical climate, including a dry season (Gomez et al, 2003).…”