Le Naturaliste Vendéen, Numéro 3 (2003)
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A micro-crustacean has recently been discovered in Vendée. It is an Ostracod living in temporary bodies of slightly brackish or fresh water. From the Cyprididae family, Cypris bispinosa is a crustacean whose presence in France is only known from eight countess. It is however one of our largest ostracods, and the lateral spine fixed on each side of its carapace make the species easily recognisable with a lens.
In 1869 Tacite Letourneux described a new species of gasteropod, Valvata bourguignati, in a spring in south-east Vendée. The name of this new species was later considered to be synonymous with Neohoratia globulina. Recent samplings in the Locus typicus have permitted the revision of this taxon, now named Islamia moquiniana.
On the intertidal zone of Le Veillon at Talmond-Saint-Hilaire (Vendée, France), in 1963 Gilbert Bessonnat discovered traces of vertebrate footprints in a Hettangian formation. On March 28th & 29th, at this site a study session was held on the theme: "sites with vertebrate footprints on the Triassic-Jurassic limit". Palæontologists, palæobotanists, sedimentologists, hydrologists, scientific historians and naturalists compared their results and projected further research. This exceptional Vendée heritage site is to be protected and developed.
It has been forty years since the Jurassic site of Veillon in Talmont-Saint-Hilaire (Vendée, France), where footprints of vertebrates were found, was plundered. This outstanding site belonging to Vendée's geological patrimony needs to be preserved and developed. Some footprints from Veillon are displayed in the collections of about thirty public institutions and six museums.
The Liassic Talmont-Saint-Hilaire (Vendée, France) outcrop has been studied here according to the abundance of fossil plants of the Cheirolepidiaceous family (Gymnosperms, Coniferales). A new species of Brachyphyllum has been studied in light microscopy, even in scanning electron microscopy and transmission electron microscopy. It is, at that time, one of the most complete study realized on a fossil taxon. Epidermal cells, subsidiary cells and guard cells have been described on both adaxial and abaxial surfaces, in transversal and longitudinal sections. Cuticle ultrastructural variations have been observed between epidermal and stomatal cells. To conclude, we propose a discussion about the cuticle structure variations related to environmental conditions and the functional morphology of the different cells.
Palichnites et muséologie
(2003)
After they had intrigued the inquiring or observant mind for decades, it was realised that certain "natural curiosities" were tracks of extinct creatures, related to gigantic birds or other antediluvian animals. At the beginning of the XIXth century a new science, ichnology, came into being and developed, thanks to the collection, preservation and study of fossil prints. The increasing quantity of evidence thus unearthed reveals the diversity of vertebrate faunas which have trod the earth’s surface and left behind valuable information about their characteristics and behaviour. Like other institutions labouring on behalf of conservation, knowledge of nature and the preservation of our natural heritage, the Nantes Natural History Museum has, for nearly two centuries, collected, conserved, displayed and brought to the attention of the public those valuable pieces of evidence, fossil footprints. Displays of fossil prints are regularly presented during different exhibitions. Examples of them permit one to follow the evolution of our knowledge of these prints and illustrate how the information yielded by these prints has been transmitted.
Using the fossil dinosaur footprints of the lower Lias of Le Veillon at Talmont-Saint-Hilaire, (Vendée) as a starting point, the reconstitution by pupils of a unique fossil-bearing site is under consideration. The paleobiology and paleoecology of reptiles in this geological site are dealt with.
In the Talmondais (Vendée) the Hettangian sedimentation locally begins with fluviatil clastic deposits prior to the deposition of shallow marine carbonates. These clastics, including the footprint-bearing beds of Le Veillon (south of Talmont- Saint-Hilaire) are subject to important and frequent variations in thickness. Drilling and geophysic data indicate a tectonic control of these variations. A fault-block pattern is proposed. At a small scale, it gives an illustration of the extensional tectonic processes related to the evolution of the Biscay rift during the early Liassic.
The Veillon ichnofauna, early Liassic in age, includes various Reptile taxa: quadruped Pseudosuchian, Coelurosaurians, Theropods, primitive Iguanodon – like Ornithopods and some unspecified forms. This ichnofauna is very comparable to the early Liassic footprint assemblage of the Connecticut.
One of the remaining French otter populations lives on Noirmoutier island where the marine environment offers food resources. A study of the otters' diets will prove if these resources are used or not.