Palaeastacus Bell, 1850

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 : 525

Genus Palaeastacus Bell, 1850

( Fig. 1G, H )

Palaeastacus Bell, 1850: 344 . — Zittel 1885: 695. — Beurlen 1928: 180. — Förster 1966: 126. — Taylor 1979: 26. — Aguirre-Urreta & Ramos 1981: 606. — Aguirre-Urreta 1989: 509. — Schweitzer & Feldmann 2001: 174. — Feldmann et al. 2015: 3. — Hyžný et al. 2015: 375.

Enoploclytia (Palaeastacus) – Mertin 1941: 161. — Glaessner 1969: 455.

TYPE SPECIES. — Astacus sussexiensis Mantell, 1824 , by subsequent designation of Glaessner (1929).

EMENDED DIAGNOSIS. — Fusiform intercalated plate with tubercles; 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 nearly parallel, both joined to hepatic groove; concavo-convex hepatic groove, joined to cervical groove; inferior groove convex posteriorly, joined to hepatic groove; longitudinal rows of sub-spiny tubercles in gastric region, diagonal rows of tubercles on cardiac region; massive chelate P1; P1 propodus short, thick, slightly globose, inner margin more compressed than outer margin, longitudinal rows of spiny tubercles on dorsal and ventral surfaces, inner margin bearing strong spines; P1 palm with narrow dactylar bulge; wide fingers, slightly longer than propodus, gradually narrowing to distal extremity; index with basally curved occlusal margin.

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.