The Paleocene-Eocene Thermal Maximum (PETM) is correlated with the first occurrences of earliest modern mammals in the Northern Hemisphere. The latest Paleocene Clarkforkian North American Land Mammal Age, that has yielded rodents and carnivorans, is the only exception to this rule. However, until now no pre-PETM localities have yielded modern mammals in Europe or Asia. We report the first Clarkforkian equivalent Land Mammal Age in the latest Paleocene deposits of the basal Sparnacian facies at Rivecourt, in the north-central part of the Paris Basin. The new terrestrial vertebrate and macroflora assemblages are analyzed through a multidisciplinary study including sedimentologic, stratigraphic, isotopic, and palynological aspects in order to reconstruct the paleoenvironment and to evaluate biochronologic and paleogeographic implications. The mammals are moderately diverse and not abundant, contrary to turtles and champsosaurs. The macroflora is exceptional in preservation and diversity with numerous angiosperms represented by flowers, fruits, seeds and wood preserved as lignite material, revealing an abundance of Arecaceae, Betulaceae, Icacinaceae, Menispermaceae, Vitaceae and probably Cornaceae. Results indicate a Late Paleocene age based on carbon isotope data, palynology and vertebrate occurrences such as the choristoderan Champsosaurus, the arctocyonid Arctocyon, and the plesiadapid Plesiadapis tricuspidens. However, several mammal species compare better with the earliest Eocene. Among these, the particular louisinid Teilhardimys musculus, also recorded from the latest Paleocene of the Spanish Pyrenees, suggests a younger age than the typical MP6 reference level. Nevertheless, the most important aspect of the Rivecourt fauna is the presence of dental remains of a rodent and a “miacid” carnivoran, attesting to the presence of two modern mammalian orders in the latest Paleocene of Europe. Interestingly, these two groups are also the only modern groups recorded from the latest Paleocene of North America, making Rivecourt the first direct equivalent to the Clarkforkian Land Mammal Age outside of North America.

Some tribes are easy to identify (Borasseae, Cryosophileae, Phoeniceae, Caryoteae); others are rather heterogeneous and more difficult to define (Chuniophoeniceae, Trachycarpeae). Caryoteae presents some unique states of the Arecoideae.

The Upper Cretaceous lignite deposits of La Garnache, Vendée (western France), consist of two lignitic clay series, Garnache 1 and Garnache 2, separated by a fault. The first series cropped out to the south of the fault during road works until 2002 but is now covered by an embankment. It has provided numerous pieces of amber containing arthropod and micro-organism inclusions. The second lignitic series, exposed to the north of the fault, is rich in fossil wood but devoid of amber. Palynological analysis of Garnache 1 revealed several Normapolles species belonging to the genera Atlantopollis, Complexiopollis, Osculapollis, Plicapollis and Trudopollis, but larger forms typical of Senonian deposits are absent. By contrast, Garnache 2 proved to be dominated taxonomically and numerically by spores (Appendicisporites, Camarozonosporites, Gleicheniidites, Patellasporites, Stereisporites), associated with a few gymnosperm (Cerebropollenites, Phyllocladidites, Classopollis) and angiosperm (Liliacidites, Retitricolpites and a single specimen of the Normapolles Complexiopollis) taxa. Garnache 1 is, therefore, younger than Garnache 2, the latter being clearly Cenomanian in age whereas Garnache 1 is more likely to be Turonian. Lignitic clay of Garnache 1 contains numerous translucent, orange to red, pieces of amber. Vendean amber is rich in aquatic arthropods, such as tanaids and epicarideans (Crustacea), as well as marine or brackish siliceous micro-organisms such as diatoms and sponge spicules. These aquatic inclusions indicate that resin-producing trees grew along and close to the seashore. The amber-bearing clay was deposited in a calm, estuarine or lagoonal, muddy environment.

The diversity of palm stem anatomy is now well known, but no study has dealt with the influence of climatic conditions. Here, we conducted research in order to establish whether this diversity follows a phylogenetic pattern and/or whether it is correlated with climatic factors. To answer this question, 98 genera and 137 species that cover the five palm subfamilies were sampled. Anatomical descriptors and measurements of vessel diameter were used in multiple correspondence analyses (MCAs) and hierarchical clustering in order to analyse correspondences between anatomy and climate [tropical rain forest (TRF) palms vs. palms growing in a climate with a dry period]. Qualitative anatomical descriptors were plotted on a recent phylogenetic tree. MCA outlined correlations between:(1) one-vessel palms and TRF palms; (2) two-vessel palms and 'dry period' palms; (3) small vessel diameter (< 144 μm) and 'dry period' palms; and (4) large vessel diameter (> 183 μm) and TRF palms. From phylogenetic analyses, Arecoideae (and, to a lesser extent, Calamoideae) is defined as the one-vessel subfamily, Coryphoideae as the two-vessel subfamily and Ceroxyloideae with three to several vessels per fibrous vascular bundle. Palm stem anatomy is thus correlated with climate (TRF vs. non-TRF), but also shows a phylogenetic signal. Therefore, it suggests that the diversification of Arecoideae and Coryphoideae coincided with the beginning of their ecological dominance. Baker WJ, Savolainen V, Asmussen-Lange CB, Chase MW, Dransfield J, Forest F, Harley MM, Uhl N, Wilkinson M. 2009. Complete generic-level phylogenetic analyses of palms (Arecaceae) with comparisons of supertree and supermatrix approaches. Systematic Biology 58: 240-256. Barrow SC. 1998. A monograph of Phoenix L. (Palmae: Coryphoideae). Kew Bulletin 53: 513-575. Bayton RP. 2007. A revision of Borassus L. (Arecaceae). Kew Bulletin 62: 561-585. Blach-Overgaard A, Kissling WD, Dransfield J, Balslev H, Svenning JC. 2013. Multimillion-year climatic effects on palm species diversity in Africa.