SI Appendix The oldest modern therian mammal from Europe and its bearing on stem marsupial paleobiogeography RomainVulloa,b,1, Emmanuel Gheerbrantc, Christian de Muizonc, Didier Néraudeaub Table of contents • Part I. List of characters studied. • Part II. Character matrix. • Part III. TNT analysis, cladograms, and characters at nodes. • Part IV. References. Part I List of characters studied (mostly molars) All characters are additive, except when mentioned. 1. Molar cusp shape: sharp, gracile (0), low but still acute (1), or inflated, robust, low, bulbous (2). Arcantiodelphys (1). 2. Protocone: lacking (undifferentiated from the lingual cingulum) (0), incipient (very small) but inflated with protocristae and functionnal (1), or well developed, with large protofossa (2). Arcantiodelphys (2). Kielantherium : upper molars features are based on the new material reported by Lopatin and Averianov (1). 3. Stylar shelf: wide (0), very wide (1), or narrow (2). Arcantiodelphys (0). Character non additive. 4. Protocone development: mesio-distally narrow and compressed (0) or well-developed (both mesio-distally and labio-lingually) and uncompressed (1). Arcantiodelphys (1). 5. Height of the protocone relative to the paracone and metacone (whichever is highest of the latter two): protocone markedly lower (less than 70%) (0), protocone of intermediate height (70%~80%) (1), or protocone near the height of paracone and metacone (within 80%) (2). Arcantiodelphys (2). 6. Stylar cusp C: absent (0), present but weak (1), or present and well developed (2). Arcantiodelphys (1). 7. Stylar cusp D: absent (0), present but weak (1), or present and well developed (2). Arcantiodelphys (1). 8. Paraconule and metaconule: absent or weak (0) or present and well developed (1). Arcantiodelphys (0). Prokennalestes: well developed paraconule, but weak metaconule. Deltatheridium conules weak to absent (deltatheroidan ancestral morphotype = conules probably absent; e.g., ref. 2). 9. Postprotocrista: labial extension of the postprotocrista at the distal base of the metacone: absent (0) or present (1). Arcantiodelphys (0). 10. Height and size of the paracone and metacone: paracone noticeably higher and larger at the base than metacone (0), paracone slightly higher and larger than metacone (1), or paracone and metacone subequal in size or paracone lower than metacone (2). Arcantiodelphys (1-2). 11. Metacone and paracone bases: merged (0) or separated (1). Arcantiodelphys (1). In Asiatherium, the paracone and metacone are fused in M1-2/, but separated in M3-4/. 12. Postmetacrista length: long (0), very long (1), or absent or short (2). Arcantiodelphys (0). 13. Postmetacrista sharpness and height: low and blunt (0) or high and salient (1). Arcantiodelphys (0). 14. Mesiodistal position of the protocone: more or less centrally placed (lingually between the metacone and the paracone) (0), lingual to the paracone but not significantly procumbent (1), or noticeably anterior (lingual to at least paracone apex) and procumbent (2). Arcantiodelphys (0). 15. Lingual cingulum: absent (0) or present (1). Arcantiodelphys (0). 16. Talonid morphology: small heel (0) or multicusped basin (1). Arcantiodelphys (1). 17. Trigonid height relative to talonid height: twice or more (0), less than twice (1), or subequal (2). Arcantiodelphys (1). 18. Antero-posterior compression of the trigonid of the m1: absent (0) or present (1). Arcantiodelphys (0). 19. Paraconid keel or cusp e: present (0) or absent (1). Arcantiodelphys (0). 20. Paracristid: presence of a widely V-shaped notch (0) or presence of a deep carnassial notch (1). Arcantiodelphys (0). 21. Relative height and size of the paraconid and metaconid: paraconid distinctively higher than the metaconid (0), paraconid and metaconid subequal in height or paraconid slightly smaller than metaconid (1), or paraconid much smaller than metaconid (2). Arcantiodelphys (1). 22. Labio-lingual position of the paraconid relative to the metaconid (based on the lower second molar): paraconid lingual as the metaconid (0) or paraconid distinctly shifted labially (1). Arcantiodelphys (0). 23. Relative height of the protoconid: protoconid high (0) or protoconid low (1). Arcantiodelphys (1). 24. Lingual crests in the trigonid of anteriormost lower molars: absent (0) or present (1). Arcantiodelphys (1). 25. Lingual crests in the trigonid of posterior lower molars: absent (0) or present (1). Arcantiodelphys (0). 26. Metaconid-protoconid relative position: metaconid distal to protoconid (0) or metaconid aligned transversely with protoconid (protocristid transversal) (1). Arcantiodelphys (1). 27. Cristid obliqua: contact below the metaconid (0), contact below the protocristid notch (1), or contact below the protoconid (2). Arcantiodelphys (2). 28. Hypoflexid: very deep (0), deep (40~50% of talonid width) (1), or absent or shallow (>65%) (2). Arcantiodelphys (2). 29. Postmetacristid: present (0) or absent (1). Arcantiodelphys (0). Deltatheroidans: 29(0) (Cifelli and Muizon, 1997) 30. Talonid width relative to trigonid width: very narrow (<40% trigonid width) (0), narrow (40- 70% trigonid width) (1), or subequal to wider (2). Arcantiodelphys (2). 31. Hypoconulid: in median position (0), approximated to the entoconid (1), or twinned with the entoconid (2). Arcantiodelphys (1). 32. Entoconid size (anterior molars): absent (0), smaller than (1), or subequal to hypoconulid (2), larger than hypoconulid (3). Arcantiodelphys (2). 33. Hypoconid labial face: angular (compressed mesio-distally) (0) or basically rounded (uncompressed) (1). Arcantiodelphys (0). 34. Postcingulid: absent (0) or present (1). Arcantiodelphys (0). 35. Abrasion (horizontal wear facet): absent (0) or present (1). Arcantiodelphys (1). 36. Grinding wear facet 9: absent (0) or present (1). Arcantiodelphys (1). 37. Number of lower molars: four (0), four but last molar reduced (1), or three (2). Arcantiodelphys (?). Only three lower molars were illustrated and reported in Sinodelphys szalayi by Luo et al. (3), by contrast to the four upper molars described in the same species. Such a disparity in upper and lower molars number is very unusual, and mechanically unlikely (disocclusion of molars). Our observation of the cast of Sinodelphys suggests that there are four lower molars, and four or three lower premolars. The lower tooth homologous of the P2/ seen in Sinodelphys (smallest premolar in the taxon) is unobserved either because it is truly absent or because it is unpreserved (with location in the large diastema figured by Luo et al. (3: fig. 1 D). 38. Number of lower premolars: five or more (0), four (1), or three (2). Arcantiodelphys (?). 39. Number of upper molars: four (0), four but last molar reduced (1), or three (2). Arcantiodelphys (?). 40. Number of upper premolars: five or more (0), four (1), or three (2). Arcantiodelphys (?). Part II Matrix of characters analyzed Characters are treated as additive, except when mentioned. 1 2 3 4 5 6 7 8 9 1 0 1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 Peramus 0 0 0 - - 0 0 0 - 0 0 1 1 - 0 0 0 0 0 Kielantherium 0 1 0 0 0 0 0 0 - 0 0 1 0 1 0 1 0 0 0 Holoclemensia 0 2 0 0 1 2 2 1 0 0 0 0 0 0 0 1 0 1 0 Prokennalestes 0 2 2 0 0 0 1 1 1 0 0 1 1 1-2 0 1 0 1 1 Maelestes 0 2 2 0 0 0 0 0 1 0 0 1 1 1-2 1 1 0 1 1 Sinodelphys 0 2 0 ? ? 0 1 ? ? 1 0 ? ? ? ? 1 0 0 ? Deltatheridium 0 2 1 0 0 0 0 1 0 1 0 2 1 0-1 0 1 0 0 0 Kokopellia 0 2 0 1 0 0 1 1 1 1 ? 1 1 1 0 1 0 0 0 Arcantiodelphys 2 2 0 1 2 1 1 0 0 1-2 1 0 0 0 0 1 1 0 0 Asiatherium 0 2 2 0 0 0 1 1 1 1 0-1 0 1 1 1 1 1 0 1 Iugomortiferum 2 2 0 1 ? 1 1 0 1 2 1 1 0 1 0 1 1 0 0 Adelodelphys 0 2 0 1 1 1 1 1 1 2 0 1 1 1 0 1 1 ? ? Sinbadelphys 0 2 0 1 ? 1 1 1 1 2 1 1 1 1 0 1 0 0 0 Dakotadens 1 2 0 1 2 2 2 0 0 2 1 1 0 0 0 1 1 0 0 Pariadens 0 2 0 1 2 2 2 1 1 2 1 1 1 0-1 0 1 0 0 0 Didelphis 1-2 2 0 1 2 2 2 0 0 2 1 1 1 2 0 1 1 0 0 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Peramus ? 0 0 0 0 0 0 0 0 1 0 - 0 ? 0 0 - 2 0 0 2 Kielantherium 1 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0-1 ? ? Holoclemensia ? 2 1 0 ? 0 1 0 0 ? 1 0 2 0 0 0 0 ? ? ? ? Prokennalestes 0 2 1 0 0 0 1 0 0 1 1 0 1 0 0 0 0 2 0 2 ? Maelestes 0 2 1 0 0 0 1 1 1 1 1 0 2 0 0 0 0 2 1 2 0 Sinodelphys ? 1 0 1 ? ? ? 0 0 ? 1 1 1 0 0 0 1-2 0 1 0 1 Deltatheridium 1 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 1 2 1 2 Kokopellia 1 1 0 0 0 0 0 1 1-2 0 2 1 2 0 1 0 0 0 2 ? ? Arcantiodelphys 0 1 0 1 1 0 1 2 2 0 2 1 3 0 0 1 1 ? ? ? ? Asiatherium 1 1 0 1 0 0 1 1-2 1-2 1 2 1 2 0 1 0 0 0 2 0 2 Iugomortiferum ? 1 0 1 0 0 1 1 1 0 2 2 3 0 1 1 0 ? ? ? ? Adelodelphys ? 1 0 ? ? ? ? 1 1 ? 2 1 3 0 1 0 0 ? ? ? ? Sinbadelphys 1 1 0 0 0 0 0 1 1 0-1 2 2 3 0 1 0 0 ? ? ? ? Dakotadens 0 1 0 1 1 1 1 2 2 0 2 2 3 1 0 1 0 ? ? ? ? Pariadens 1 0 0 0 0 0 0 1 1 0 2 2 3 1 1 0 0 0 ? ? ? Didelphis 1 1 0 0 0 0 1 2 2 1 2 2 3 1 0 0 0 0 2 0 2 Part III TNT Analysis (4) Matrix, 40 characters x 16 taxa.