Mesolimulus walchii ( Desmarest, 1817 )

Odin, Giliane P., Charbonnier, Sylvain, Devillez, Julien & Schweigert, Günter, 2019, On unreported historical specimens of marine arthropods from the Solnhofen and Nusplingen Lithographic Limestones (Late Jurassic, Germany) housed at the Muséum national d’Histoire naturelle, Paris, Geodiversitas 41 (17), pp. 643-662 : 658

Mesolimulus walchii ( Desmarest, 1817) ( Fig. 11 )

STUDIED MATERIAL. — Charbonnier & Garassino (2012) listed four specimens from Solnhofen (MNHN.F. A33516 , B13432, B13433; MNHN.GG.2004/7473) but figured only one specimen (MNHN.F. A33516 ). We do not change their contribution.

COMMENTS

Specimen MNHN.F.B13432 ( Fig. 11A ) is poorly preserved and exhibit many calcite bundles (as dumbells and spheres), mostly at the rear of the prosoma.According to Briggs & Wilby (1996), among the arthropods of Solnhofen, Mesolimulus is the taxon the most commonly subject to calcite crystals bundles development (we illustrate a specimen of Eryon cuvieri with calcite bundles on Fig. 9B ). Such crystals are believed to be formed during the early stage of diagenesis, due to microbial activity. Specimen MNHN.F.B13433 ( Fig. 11B ) is a dorsal view of a slightly deformed specimen; the prosoma, carapace and telson are beautifully preserved.

Acknowledgements

We thank Lilian Cazes (CR2P, MNHN) for assistance in photographic work. This paper is a contribution from the UMR CNRS 7207 Centre de Recherche en Paléontologie – Paris, and part of the ‘PyrEx’ project, funded by the DIM Matériaux Anciens et Patrimoniaux. We also would like to thank Denis Audo and Alessandro Garassino for their useful comments on a previous version of the manuscript.

Figures

FIG. 11. — Mesolimulus walchii (Desmarest,1817):A, specimen MNHN.F.B13432; B, specimen MNHN.F.B13433. Scale bar:1 cm.Photographs:L.Cazes.

FIG. 9. — A, Cycleryon propinquus (Schlotheim,1822):specimen MNHN.F.B13436 from Solnhofen;B-H, Eryon cuvieri Desmarest,1817:B, specimen MNHN.F.A33501 from Solnhofen;C, specimen MNHN.GG.2004/8218 from Solnhofen area;this specimen was referred to as coming from Pappenheim;since there are no Solnhofen Lithographic Limestones there, while many traders lived there, this specimen was probably purchased in Pappenheim; D, E, specimen MNHN.GG.2004/8220 from Solnhofen, natural light (D) and UV light (E); F, G, specimen MNHN.F.A33545 from Solnhofen, natural light (F) and UV light (G); H, specimen MNHN.F.B13439 from unknown locality. Scale bars: A, C, F, H, 2 cm; B, D, E, F, 1 cm. Photographs: L. Cazes.