Pleurohoplites Spath, 1921

Barroso-Barcenilla, Fernando, Antunes, Miguel Telles, Brandão, José Manuel, Callapez, Pedro Miguel, Santos, Vanda Faria dos & Segura, Manuel, 2018, The d’Orbigny Palaeontological Collection of the National Museum of Natural History and Science, Lisbon, Portugal: Historical perspective and revision of Cretaceous Cephalopoda, Geodiversitas 40 (20), pp. 505-519 : 512

Genus Pleurohoplites Spath, 1921

Subgenus Pleurohoplites (Pleurohoplites) Spath, 1921

Pleurohoplites (Pleurohoplites) renauxianus (d’Orbigny, 1840) ( Fig. 3E, F )

MATERIAL. — An internal mould with matrix and without written or glued indications. Original label: Nº 464/ Ammonites Renauxianus (d’Orb), Andar 20º Cenomaniense, Terreno Cretaceo, Localidade Mont-Blainville (Meuse). See Figs 1D; 3G.

DESCRIPTION

A medium-sized,compressed and moderately involute ammonite with suboval whorl section. Bended venter and flat flanks, and wide umbilici with arched walls. Ornamentation formed by approximately 15 small umbilical bullae per whorl that give rise to pairs of tenuous and proverse ribs. These ribs are straight on the inner flanks and projected on the outer flanks and the venter, thickening on the venterolateral margins, where they resemble to blunt and oblique nodes. Nearly unobservable suture lines.

DISCUSSION

This upper Albian species was firstly reported in Mont-Blainville (Meuse), France, by d’Orbigny (1850: 145). Some other close species of the genus are P. subvarians Spath, 1928 , P. epigonus Spath, 1928 , P. serpentinus Spath, 1928 , and P. robusticostatus Immel & Guoxiong, 2002 , usually with stronger ribbing. In the last years, P. (P.) renauxianus , type of the genus, has been studied byLatil (1995), Fischer & Gauthier (2006) and Kennedy & Latil (2007), among others.

Family ACANTHOCERATIDAE de Grossouvre, 1894

Figures

FIG. 3. — Cretaceous ammonites of the d’Orbigny Collection of the National Museum of Natural History and Science (Museu Nacional de História Natural e da Ciência): A-D, Neolissoceras grasianum (d’Orbigny, 1840) in ventral (A), lateral (B) and oral (C) views, and original label (D): Nº 357/Ammonites grasanus (d’Orb), Andar 17º Neocomiense, Terreno Cretaceo, Localidade S.t Julien (Hautes Alpes); E-G, Pleurohoplites (Pleurohoplites) renauxianus (d’Orbigny, 1840) in lateral (E) and ventral (F) views, and original label (G): Nº 464/Ammonites Renauxianus (d’Orb), Andar 20º Cenomaniense, Terreno Cretaceo, Localidade Mont-Blainville (Meuse); H-K, Acanthoceras rhotomagense (Brongniart, 1822) in oral (H), lateral (I) and ventral (J) views, and original label (K): Nº 463/Ammonites rhotomagensis (Lamarck), Andar 20º Cenomaniense, Terreno Cretaceo, Localidade Rouen (Seine inf.re). Scale bar: 2 cm.