Palaeastacus Bell, 1850

Devillez, Julien & Charbonnier, Sylvain, 2021, Review of the Late Jurassic erymoid lobsters (Crustacea: Decapoda), Geodiversitas 43 (2), pp. 25-73 : 49

Genus Palaeastacus Bell, 1850

( Fig. 1 F-G)

Palaeastacus Bell, 1850: 344 . — Zittel 1885: 695. — Beurlen 1928: 180. — Förster 1966: 126. — Glaessner 1969: 626. — Aguirre-Urreta & Ramos 1981: 606. — Aguirre-Urreta 1989: 509. — Schweitzer & Feldmann 2001: 174. — Feldmann et al. 2015: 3. — Hyžný et al. 2015: 375. — Devillez et al. 2016: 525 , fig. 1G-H. — Devillez et al. 2017: 782.

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

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

DIAGNOSIS BY Devillez & Charbonnier (2019). — 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 the cervical groove; postcervical and branchiocardiac grooves subparallel, joined to hepatic groove; hepatic groove concavo-convex, joined to cervical groove; inferior groove convex posteriorly, joined to hepatic groove; chelate P1; P1 propodus short, thick, slightly globose, with a narrow dactylar bulge; P1 fingers usually wide, slightly longer than propodus, progressively narrowing to their distal extremity, occlusal margin curved at the basis of the index.

Figures

FIG. 1. — Carapace and P1 chela morphologies of the Late Jurassic erymoids: A, regions of the carapace; B, morphology of a chela of the first pair of pereiopods; C, typical carapace groove pattern of Eryma; D, form I of chela of the first pair of pereiopods of Eryma; E, form II of chela of the first pair of pereiopods of Eryma; F, typical carapace groove pattern of Palaeastacus; G, typical chela of the first pair of pereiopods of Palaeastacus; H, typical carapace groove pattern of Pustulina; I, typical chela of the first pair of pereiopods of Pustulina; J, typical carapace groove pattern of Stenodactylina; K, form I of chela of the first pair of pereiopods of Stenodactylina; L, form II of chela of the first pair of pereiopods of Stenodactylina; F, typical carapace groove pattern of Enoploclytia; G, typical chela of the first pair of pereiopods of Enoploclytia. Abbreviations: a, branchiocardiac groove; ar, antennal region; b, antennal groove; b1, hepatic groove; br, branchial region; c, postcervical groove; cr, cardiac region; d, gastro-orbital groove; e1e, cervical groove; gr, gastric region; hr, hepatic region; i, inferior groove; ip, intercalated plate; PoA, post-orbital area; pr, pterygostomial region; χ, attachment site of adductor testis muscle; ω, attachment site of mandibular muscle. Line drawings: J. Devillez.