Enoploclytia M’Coy, 1849

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 : 530

Genus Enoploclytia M’Coy, 1849

( Fig. 1I, J )

Enoploclytia M’Coy, 1849: 330 ; 1854: 137. — Zittel 1885: 694. — Fritsch & Kafka 1887: 27. — Van Straelen 1925: 278. — Beurlen 1928: 164. — Rathbun 1926: 128. — Secrétan 1964: 81. — Förster 1966: 146. — Taylor 1979: 25. — Aguirre-Urreta 1989: 514. — Feldmann et al. 2015: 3.

Enoploclytia (Enoploclytia) – Mertin 1941: 160. — Glaessner 1969: 455.

TYPE SPECIES. — Astacus leachii Mantell, 1822 , by original designation.

EMENDED DIAGNOSIS. — Fusiform intercalated plate; wide, deep cervical groove, joined to dorsal margin and to antennal groove; long, wide gastro-orbital groove originating as median inflexion of cervical groove, delimiting two gastro-orbital lobes; sinuous postcervical groove, joined to dorsal margin and to hepatic groove, with ventral extension at carapace mid-height; short branchiocardiac groove, interrupted in upper part of carapace, joined to dorsal margin, not joined to postcervical groove; concavo-convex hepatic groove, joined to cervical groove; prominent ω and χ bulges; inferior groove convex posteriorly, joined to hepatic groove; carapace with heterogeneous coarse ornamentation; massive globose P1 propodus, rounded in transversal section; long and thin P1 fingers (straight in dorsal view); occlusal margins armed with sharp and slender tooth.

PRELIMINARY REMARKS

Out of numerous species of Enoploclytia listed by Schweitzer et al. (2010), five are known from the Early Cretaceous.Among these species, two are from the Hauterivian of France: Enoploclytia glaessneri Van Straelen,1936 , which belongs to Eryma (see comments about Eryma glaessneri ), and Enoploclytia salviensis (Robineau-Desvoidy, 1849) . The type material of E. salviensis is lost for a long time and the species is only known by the figures presented byRobineau-Desvoidy (1849): some fragments of P1 fingers and a carapace. The fragments of fingers are curved with numerous short and close teeth, while fingers of Enoploclytia are straight with long, slender and spaced teeth. Furthermore, the illustrations of the carapace is not clear enough to assign it to any genus of decapod crustaceans.

Two other species come from the Albian of Texas. Enoploclytia wintoni Stenzel, 1945 is known by a pair of chelae with globose and coarsely tuberculate propodus and slender denticulate fingers typical of Enoploclytia . Enoploclytia wenoensis Rathbun, 1935 , is known by a single pleon with terga without relief, densely covered with small pits and rounded pleura. Usually species of Enoploclytia have a pleon with more relief (longitudinal bulges on pleura basis; coarse, widely spaced ornamentation) and triangular, sharp pleura. Then, following Stenzel (1945) and Förster (1966), we conclude that E. wenoensis is probably not a representative of Enoploclytia but maybe a representative of Astacodes Bell, 1863 , Hoploparia M’Coy, 1849 , or Homarus Weber, 1795 .

Enoploclytia tenuidigitata Woods, 1957 (Aptian of Queensland, Australia) is known by some fragments of carapace, P1 chelae and pleon. The carapace groove pattern with postcervical and branchiocardiac grooves joined to hepatic groove is typical of Palaeastacus . So E. tenuidigitata should be assigned to Palaeastacus ; thus a new combination Palaeastacus tenuidigitatus ( Woods, 1957) , n. comb. is proposed herein.

Taylor (1979),Aguirre-Urreta(1982)andGarassino etal. (2009) reported fragments of chelae attributed to Enoploclytia sp. from the Aptian of Alexander Island (Antarctic), the Barremian of Patagonia ( Argentina) and the Aptian of Catalonia ( Spain), respectively. Finally, E. wintoni and the fragments of chelae discussed above have until now been the only reports of Enoploclytia from the Early Cretaceous.

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.