Morphology of the carapace and of the chela of the first pair of pereiopods of Eryma Meyer, 1840a and Eryma sinemurianum (Garassino, 1996). A: typical carapace groove pattern of Eryma; B: form I of chela of the first pair of pereiopods of Eryma; C: form II of chela of the first pair of pereiopods of Eryma; D–E: holotype MSNM i13517 of Eryma sinemurianum from the Sinemurian of Osteno (Italy): general view (D), line drawing (E); F: paratype MSNM il7608 of E. sinemurianum, G: paratype MSNM il0450. Scale bars: 1 cm. Abbreviations: a: branchiocardiac groove; b: antennal groove; b₁: hepatic groove; c: postcervical groove; d: gastro-orbital groove; di: diaeresis; e: eyes; e₁e: cervical groove; i: inferior groove; ip: intercalated plate; Mxp3: third maxillipeds; P1–2: pereiopods; PoA: post-orbital area; s3–6: pleonal somites; sc: scaphocerite; tl: telson; χ: attachment site of adductor testis muscle; ω: attachement site of mandibular muscle. Photographs: A. Garassino. Line drawings: J. Devillez.