Glypheopsis trouvillensis Charbonnier, Garassino, Schweigert & Simpson, 2013

Charbonnier, Sylvain, Garassino, Alessandro, Gendry, Damien, Devillez, Julien & Picot, Laurent, 2023, The decapod crustacean fauna from the Late Jurassic of Cricqueboeuf, Normandy (France), Geodiversitas 45 (19), pp. 573-588 : 576

Glypheopsis trouvillensis Charbonnier, Garassino, Schweigert & Simpson, 2013 ( Figs 2 ; 3 )

Glypheopsis trouvillensis Charbonnier, Garassino, Schweigert & Simpson, 2013: 153 , 154, fig. 331, table 5.

TYPE MATERIAL. — Holotype FSL-EM 80052 .

TYPE LOCALITY. — Trouville-sur-Mer, Calvados, Normandy, France.

TYPE AGE. — Late Jurassic (late Oxfordian).

ADDITIONAL EXAMINED MATERIAL. — 24 specimens ( MPV 2013.1.146.1-21 , 2013.1.288.3 , Hurtrelle coll.; IGR-PAL-153416 , 153417 , Bara coll.) from the Oxfordian of Cricqueboeuf , Calvados, France .

DESCRIPTION

See Charbonnier et al. (2013). Glypheopsis trouvillensis was described based upon one isolated carapace, which is probably a moulted specimen.Two new specimens (MPV 2013.1.146.1, 2) allow us to add some morphological details previously not provided in the original description.

Pleon

Subrectangular s1-s5 equal in size, with smooth tergum and pleuron; rounded s1-s5 pleura; s2-s5 pleura with marginal carina limited by a groove.

Thoracic appendages

Partially preserved P1 lacking distal extremities (carpus, propodus, and dactylus); P2 preserves only the subsquare basis; P3-P5 preserve basis, ischium, and incomplete merus; dorsal margin of subsquare P1 basis with one spine at level of ischiobasal articulation; subtriangular P1 ischium strongly enlarged at level of ischiomeral articulation; subrectangular P1 merus; smooth outer surface of P1 ischium and merus; dorsal and ventral margins of P1 ischium and merus covered by spines arranged in parallel rows; elongate P3 merus with smooth outer surface and spiny dorsal and ventral margins.

Ornamentation of carapace

Charbonnier et al. (2013: 154) described the ornamentation of the branchial region of the carapace as made by pits dorsally and tubercles medially and ventrally and a tuberculate pterygostomial region. Some additional specimens (MPV 2013.1.146.1-9, 11, 13-15, 19-21, IGR-PAL-153416, 153417) show that the ornamentation of the branchial region is more complex with the ventral area covered by small pits, the median area by small tubercles located inside pits, and the dorsal area by large pits.

DISCUSSION

The postcervical groove joining dorsally and ventrally to branchiocardiac groove, the presence of the cardiac and intercervical grooves and the absence of the gastro-orbital groove in additional specimens are all diagnostic characters of Glypheopsis . They are assigned to G. trouvillensis because they share with the holotype the three spiny cephalic carinae and the ornamentation of cephalic, cardiac, and branchial regions. Mainly, the ornamentation of the branchial region with a progressive gradation from ventral tubercles to dorsal pits is very typical of G. trouvillensis . We add all additional specimens collected in a fossiliferous locality nearby the type locality.

Figures

FIG. 2. — Glypheopsis trouvillensis Charbonnier, Garassino, Schweigert & Simpson, 2013 from the late Oxfordian of Cricqueboeuf, Normandy: A, B, carapace MPV 2023.1.146.5 and interpretative line drawing, left lateral view; C, carapace IGR-PAL-153416, right lateral view; D, carapace MPV 2013.1.146.3, right lateral view; E, carapace MPV 2013.1.146.4, left lateral view; F, carapace MPV 2013.1.146.6, right lateral view; G-I, carapace IGR-PAL-153417, right lateral, left lateral and dorsal views. Abbreviations: a, branchiocardiac groove; ac, antennal carina; b, antennal groove; b1, hepatic groove; c, postcervical groove; cd, cardiac groove; e1e, cervical groove; gc, gastro-orbital carina; i, inferior groove; ic, intercervical groove;oc, orbital carina;Photographs:L. Cazes, except (C): D. Gendry. Line drawing: S. Charbonnier. Scale bars: 5 mm.

FIG. 3. — Glypheopsis trouvillensis Charbonnier, Garassino, Schweigert & Simpson, 2013 from the Oxfordian of Cricqueboeuf (A-C, E, F) and Trouville-sur-Mer (D), Normandy, France: A-C, subcomplete specimen MPV 2013.1.146.1 (carapace and disconnected pleon), interpretative line drawing of carapace (B), left lateral view (A), and dorsal view of pleon and posterior margin of carapace (C); D, holotype FSL-EM 80052; E, F, carapace and fragments of pereiopods MPV 2013.1.146.2, left lateral and ventral views.Abbreviations:a, branchiocardiac groove;ac, antennal carina; b, antennal groove; b1, hepatic groove; c, postcervical groove; cd, cardiac groove; e1e, cervical groove; gc, gastro-orbital carina; i, inferior groove; ic, intercervical groove; oc, orbital carina; r, rostrum. Photographs: L. Cazes, except: D, C. Lemzaouda. Line drawing: S. Charbonnier. Scale bars: 5 mm.