Eryma Meyer, 1840

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 : 652

publication ID	https://doi.org/ 10.5252/geodiversitas2019v41a17
publication LSID	urn:lsid:zoobank.org:pub:541CF827-F02E-4086-8FB0-2C0033DD429A
DOI	https://doi.org/10.5281/zenodo.3703584
persistent identifier	https://treatment.plazi.org/id/03C23C58-FFE7-FFDB-1B35-83B3FAEEF8A7
treatment provided by	Valdenar
scientific name	Eryma Meyer, 1840
status

Treatment

Genus Eryma Meyer, 1840

TYPE SPECIES. — Macrourites modestiformis Schlotheim, 1822, by subsequent designation of Glaessner(1929).

Eryma modestiforme ( Schlotheim, 1822) ( Fig. 6 View FIG )

STUDIED MATERIAL. — Charbonnier & Garassino (2012) listed eight specimens: six specimens coming from Solnhofen (MNHN.F.A33507, B13448, B13450, B13452, B13463, MNHN.GG.2004/7462), one specimen from Eichstätt (B13446) and one specimen from an unknown locality (MNHN.GG.2004/8078-7471). Only two of them were figured (MNHN.F.B13450 and B13446) ; we thus figure three other specimens ( MNHN.F.A33507, Fig. 6B; B View FIG 13452, Fig. 6E View FIG ; and B13463, Fig. 6A View FIG ) and add three new specimens, one specimen from Eichstätt ( MNHN.F.A32408, Fig. 6H View FIG ) ; one specimen from Painten ( MNHN.F.A70906, Fig. 6G View FIG ) and one specimen from an unknown locality ( MNHN.F.A70905, Fig. 6C View FIG ). Collections Boué, Schwarzchild, A. Milne-Edwards, Hoffstetter, Manchester Museum, Férussac, Sauzières .

COMMENTS

Eryma modestiforme and E. veltheimii ( Münster, 1839) are the two species encountered in the Solnhofen Lithographic Limestones, the former being the most common. E. modestiforme is known by numerous specimens, almost complete, stored notably in European palaeontological collections (e.g. Paris, Berlin, London, Brussels, Basel). Among the MNHN collection, four specimens clearly show the intercalated plate characteristic of the erymid lobsters: MNHN.F.A32408, A33507, A70905, B13463, B13450 ( Fig. 6 View FIG A-D, H; see also Charbonnier & Garassino 2012: fig. 3b). All the specimens exhibit a short P1 propodus with a dense ornamentation, allowing us to ascribe the fossils to the species E. modestiforme (the propodus is more elongate and smooth in E. veltheimii). Moreover, three specimens show additional characters, diagnostic of E. modestiforme : 1) on the specimens MNHN.F.A70905 ( Fig. 6C, D View FIG ) and B13452 ( Fig. 6E, F View FIG ), the carapace groove pattern, in particular the junction between the postcervical and the branchiocardiac grooves ( Devillez et al. 2016; Devillez & Charbonnier 2017), is easily identifiable; and 2) the morphology of the P1 chelae of the specimen MNHN.F.A32408 ( Fig. 6H View FIG ), shows a subrectangular propodus, thin fingers progressively narrowing to their distal extremity and without teeth on their occlusal margins.

The historical specimen MNHN.F.A32408, figured by Desmarest (1822: pl. 11, fig. 5), shows the typical mode of preservation and lithology of the Bavarian Lithographic Limestones ( Fig. 6H View FIG ) but the locality of this specimen may be misleading. Desmarest (1822: 136) refers to “Aichstedt”, which is also the locality indicated on the original label, while the locality “Aichtät” is specified on the specimen. In a letter about the Franconian geology to A. Brongniart, L. de Buch (1823) evokes the lithographic limestones exploited at “Eichstedt” and “Solenhofen”, in the Altmuhl valley. However, there is no locality spelled “Eichstedt” next to the Altmühl River (instead, Eichstedt (Altmark) is a city located approx. 80 km west to Berlin) but “Eichstätt”. Thus, the designations “Aichtät”, “Aichstedt” and “Eichstedt” in the mentioned publications are likely orthographic variations referring to the same locality, nowadays spelled Eichstätt.