Genus Meyeria M’Coy, 1849

TYPE SPECIES. — Astacus ornatus Phillips, 1829, original designation by M’Coy (1849: 333).

DIAGNOSIS (after Charbonnier et al. 2021). — Subcylindrical carapace, laterally compressed, with ogival-shaped cross-section; pointed rostrum; antennal-pterygostomial region with strongly concave ventral margin; cervical groove strongly oblique, ventrally joined to antennal groove, delimiting narrow cephalic region; cephalic region with generally three longitudinal carinae; postcervical and branchiocardiac grooves parallel, straight, directed toward posterior margin; postcervical groove joined ventrally to branchiocardiac groove, forming one elongate lobe; elongate and wide cardiac groove, forward-inclined, joined to postcervical groove and to dorsal margin; deep hepatic groove, curved toward posterior; short inferior groove, joined to hepatic groove and interrupted before reaching ventral margin; pleon about twice the length of carapace; subrectangular telson; pseudochelate P1, strongly elongate; P2 shorter than first; pseudochelate P3-P5 with terminal dactylus.

INCLUDED FOSSIL SPECIES. — Meyeria aragonensis (Garassino, Artal & Pasini, 2009) (Oxfordian, Spain); M. bartholomaii (Jell, Woods & Cook, 2017) (Aptian, Australia); M. crofti Ball, 1960 (Campanian, Antarctic); M. gracilis Glaessner, 1932 (Hauterivian, Germany); M. houdardi (Van Straelen, 1936) (Albian, France); M. libanotica Charbonnier, Audo, Garassino in Charbonnier, Audo, Garassino, Simpson, Gèze & Azar, 2021 (Barremian, Lebanon); M. ornata (M’Coy, 1849) (Hauterivian: United Kingdom, France, Germany, The Netherlands, Switzerland; Aptian: United Kingdom); M. hurtrelleorum n. sp. (Oxfordian, France; this work); M. rostrata (Collins & Rasmussen, 1992) (late Campanian and Maastrichtian, West Greenland); M. serratosae (Dupuy de Lôme & de La Revilla, 1956) (Jurassic, Spain).