Maxime LASSERON

Postdoctoral researcher
Temporary Lecturer and Research Assistant (ATER)

General research focus

I study the paleobiodiversity, evolution, and paleobiogeography of Mesozoic continental vertebrates, with a particular focus on microvertebrates, especially those from the Jurassic-Cretaceous transition of Africa and Western Europe. Through this approach, I aim to help fill gaps in the fossil record, particularly in Gondwana. My objective is to better understand the emergence and establishment of major groups of continental vertebrates (actinopterygians, amphibians, squamates, crocodylomorphs, dinosaurs, mammals, etc.).

Research workshops

I describe and analyze the biodiversity of fossil (micro)vertebrates, particularly amphibians, lepidosaurs, dinosaurs, and mammals, using comparative anatomy, statistical methods (e.g., biometrics, diversity, abundance, and similarity indices, discriminant analyses), and imaging techniques (e.g., scanning electron microscopy, X-ray microtomography). Based on these elements, I analyze the phylogenetic relationships (cladistic phylogeny) of these animals, their biogeographic history, and their biostratigraphic implications.

Main fieldwork sites

Angeac-Charente site (Berriasian, Lower Cretaceous) – Charente, France

Since 2015, I have been a member of the team excavating and studying the Angeac-Charente site, near Angoulême (Charente, France), the only continental Lagerstätte (site of exceptional preservation) from the Lower Cretaceous (Berriasian). This site, among the most important in Europe, has yielded over 10,000 vertebrate macrofossils (turtles, crocodylomorphs, dinosaurs, including a giant sauropod among the largest known and a herd of ornithomimosaurs) and approximately 20,000 identified vertebrate microfossils, alongside more than 70,000 unidentified remains and nearly 5,000 coprolites.

Jurassic and Cretaceous sites from the Anoual Syncline and Chott Tigri – Oriental Region, Figuig Province, Morocco

Since 2018, I have also been a member of the PalOriental project, a collaboration between the Faculty of Sciences of Mohammed First University (Oujda, Morocco), the Center for Research in Paleontology-Paris (CR2P/UMR 7207; Paris, France), the University of Rennes (Rennes, France), and the Claude Bernard-Lyon 1 University (Lyon, France). This project aims to survey, excavate, and map vertebrate-bearing sites in Morocco’s Oriental Region, spanning from the Middle Jurassic to the uppermost Cretaceous. We mainly work in the Anoual Formation (Guelb el Ahmar site), the Ksar Metlili Formation (Ksar Metlili and Guelb Rzoug sites), and the Chott Tigri Formation, which have yielded over 53,000 vertebrate microfossils, as well as dozens of turtle, crocodile, and dinosaur fossils.

Publications

Contact

Iconic publications

Aouraghe H., Chennouf R., Haddoumi H., Lasseron M., Mhamdi H., Gheerbrant E. & Martin J. E. 2024 – A new Gondwanan perspective on the Jurassic-Cretaceous transition from the Tithonian-Berriasian interval of southeastern Morocco – Cretaceous Research 162: 105932 – https://doi.org/10.1016/j.cretres.2024.105932

Pochat-Cottilloux Y., Allain R. & Lasseron M. 2022 – Microvertebrate fauna from Gadoufaoua (Niger, Aptian, Early Cretaceous) – Comptes Rendus Palevol 21 (41): 901-926 – https://doi.org/10.5852/cr-palevol2022v21a41

Allain R., Vullo R., Rozada L., Anquetin J., Bourgeais R., Goedert J., Lasseron M., Martin J. E., Pérez-García A., Peyre de Fabrègues C., Royo-Torres R., Augier D., Bailly G., Cazes L., Despres Y., Gailliègue A., Gomez B., Goussard F., Lenglet T., Vacant R., Mazan & Tournepiche J.-F. 2022 – Vertebrate paleobiodiversity of the Early Cretaceous (Berriasian) Angeac-Charente Lagerstätte (southwestern France): implications for continental faunal turnover at the J/K boundary – Geodiversitas 44 (25): 683-752 – https://doi.org/10.5252/geodiversitas2022v44a25

Lasseron M., Martin T., Allain R., Haddoumi H., Jalil N.-E., Zouhri S. & Gheerbrant E. 2022 – An African radiation of ‘Dryolestoidea’ (Donodontidae, Cladotheria) and its significance for mammalian evolution – Journal of Mammalian Evolution 29: 733-761 – https://doi.org/10.1007/s10914-022-09613-9

Lasseron M., Allain R., Gheerbrant E., Haddoumi H., Jalil N.-E., Métais G., Rage J.-C., Vullo R. & Zouhri S. 2020 – New data on the microvertebrate fauna from the Upper Jurassic or lowest Cretaceous of Ksar Metlili (Anoual Syncline, eastern Morocco) – Geological Magazine 157: 367-392 – https://doi.org/10.1017/S0016756819000761

Lasseron M. 2019 – Enigmatic teeth from the Jurassic-Cretaceous transition of Morocco: the latest known non-mammaliaforms (Synapsida, Cynodontia) from Africa ? – Comptes Rendus Palevol 18 (7): 897-907 – https://doi.org/10.1016/j.crpv.2019.05.002

2025-01-21T15:14:44+00:00

GESTIONNAIRES

ADRESSE POSTALE

Université de Poitiers – UFR SFA

PALEVOPRIM UMR CNRS 7262

Bât B35 – TSA 51106

6 rue Michel Brunet

86073 POITIERS Cedex 9

Tél. : 05 49 45 37 53