Eryma Meyer, 1840

Devillez, Julien, Charbonnier, Sylvain, Hyžný, Matúš & Leroy, Lucien, 2016, Review of the Early Cretaceous erymid lobsters (Crustacea: Decapoda) from the Western Tethys, Geodiversitas 38 (4), pp. 515-541 : 518

Genus Eryma Meyer, 1840

( Fig. 1 A-C)

Eryma Meyer, 1840a: 587 . — Oppel 1862: 20. — Zittel 1885: 693. — Van Straelen 1925: 233. — Rathbun 1926: 127. — Secrétan 1964: 61. — Förster 1966: 88. — Glaessner 1969: 455. — Aguirre-Urreta & Ramos 1981: 609. — Secrétan 1984: 516. — Aguirre-Urreta 1989: 513. — Crônier & Courville 2004: 1004. — Feldmann & Titus 2006: 63. — Feldmann & Haggart 2007: 1792. — Hyžný et al. 2015: 375. — Feldmann et al. 2015: 1.

Klytia Meyer, 1840b: 19 .

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

EMENDED DIAGNOSIS. — Fusiform intercalated plate; deep cervical groove, joined to dorsal margin and to antennal groove; short gastro-orbital groove originating as a slight median inflexion of cervical groove; postcervical and branchiocardiac grooves subparallel; postcervical groove joined medially to branchiocardiac groove (with a short ventral extension); branchiocardiac groove strongly inclined, joined to hepatic groove; concavo-convex hepatic groove, joined to cervical groove; inferior groove convex posteriorly, joined to hepatic groove; marked ω bulge; cephalic region with two divergent rows of tubercles: orbital row with strong distal spine and antennal row with strong distal antennal spine; chelate P1-P3; P1 chelipeds without prominent spines and with homogeneous ornamentation; P1 propodus dorso-ventrally compressed with narrow inner and outer margins; P1 with narrow dactylar bulge; fingers longer than P1 propodus, equal in length, narrowing gradually to distal extremity; index wider than dactylus.

COMMENTS

Some species show short P1 fingers such as Eryma modestiforme or E. punctatum Oppel, 1861 , and other species show long P1 fingers such as E. bedeltum (Quenstedt, 1857) or E. ventrosum ( Meyer, 1840) . Following Hyžný et al. (2015), we distinguish two forms chelae. Form I ( Fig. 1B ) has a short rectangular propodus with straight fingers slightly longer than the propodus; form II ( Fig. 1C ) has an elongate subrectangular or trapezoidal propodus with long fingers which are usually curved inward.

Figures

FIG. 1. — Line drawings of carapaces and P1 chelae of Early Cretaceous erymid lobsters from Western Europe: A-C, Eryma Meyer, 1840: carapace (A), P1 chela form I (B), P1 chela form II (C); D-F, Stenodactylina Beurlen, 1928: carapace (D), P1 chela form I (E), P1 chela form II (F); G-H, Palaeastacus Bell, 1850: carapace (G), P1 chela (H); I-J, Enoploclytia M’Coy, 1849: carapace (I), P1 chela (J); K-L, Pustulina Quenstedt, 1857: carapace (K), P1 chela (L); M, Tethysastacus n. gen.: carapace. Abbreviations: a, branchiocardiac groove; b, antennal groove; b1, hepatic groove; c, postcervical groove; cd, cardiac groove; d, gastro-orbital groove; e1e, cervical groove; i, inferior groove; ip, intercalated plate; PoA, post-orbital area; ω, attachment site of mandibular muscle; χ, attachment site of adductor testis muscle. Line drawings: J. Devillez and S. Charbonnier.