1. Institut des Sciences de l'Evolution (ISEM UMR 5554), Université Montpellier 2, CC 064, Place Eugène Bataillon, 34270 Montpellier Cedex 05, France
2. Muséum national d'Histoire naturelle, UMR 7207 CR2P CNRS/MNHN/UPMC, 8 rue Buffon, CP 38, 75231 Paris Cedex 05, France
3. Museum of Paleontology, The University of Michigan, Ann Arbor, MI 48109-1079, USA
4. O.D. Earth & History of life, Royal Belgian Institute of Natural History, 29 rue Vautier, 1000 Brussels, Belgium