Cainozoic Research, 17(1), pp. 23-61, June 2017 23 The lower Pliocene gastropods of Le Pigeon Blanc (Loire- Atlantique, Northwest France), 4*. Neogastropoda (in part) Frank Van Dingenen1, Luc Ceulemans2 & Bernard M. Landau3, 4 1 Cambeenboslaan A 11, B-2960 Brecht, Belgium; email: [email protected] 2 Avenue Général Naessens de Loncin 1, B-1330 Rixensart, Belgium; email: [email protected] 3 Naturalis Biodiversity Center, P.O. Box 9517, 2300 RA Leiden, Netherlands; Instituto Dom Luiz da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal; and International Health Centres, Av. Infante de Henrique 7, Areias São João, P-8200 Albufeira, Portugal; email: [email protected] 4 Corresponding author Received 25 February 2017, revised version accepted 1 April 2017 In this paper we review the Neogastropoda (in part) of the Zanclean lower Pliocene assemblage of Le Pigeon Blanc, Loire- Atlantique department, France, which we consider the ‘type’ locality for Assemblage III of Van Dingenen et al. (2015). Twenty-six species are recorded, of which three are new: Euthria palumbina nov. sp., Bartschia (Agassitula) harasewychi nov. sp., Brocchinia pigeonblancensis nov. sp. Aplus aequicostatus (Bellardi, 1877) is considered a junior subjective synonym of Aplus scaber (Millet, 1865). Fusus (Aptyxis) rostratus ligerianus Peyrot, 1938 is considered a junior subjective synonym of Aptyxis omphale (Millet, 1864). The data presented here concurs with that discussed in previous parts of this monograph, suggesting that average Sea Surface Temperatures off the NW French coast in the Zanclean lower Pliocene may have been warmer than they are at these latitudes today, possibly similar to those found today off the southern Portuguese coasts. KEY WORDS: northwestern France, lower Pliocene, Neogastropoda, new taxa Introduction Geological setting, Material and methods In this paper we continue our studies on the Neogene (see Van Dingenen et al, 2015: 75-79, figures 1, 2). gastropod fossil assemblages of northwestern France (see Ceulemans et al., 2014, 2016a, b; Van Dingenen et Abbreviations: al., 2014, 2015, 2016): Gastropods of the order Neogas- tropoda (excluding Conoidea) are revised, and the study MNHN.F Muséum national d’Histoire naturelle (collec- is restricted to the locality of Le Pigeon Blanc, which tion de Paléontologie), Paris (France). we consider to be the ‘type’ locality for Assemblage III NHMW Naturhistorisches Museum Wien collection, gastropods (of Van Dingenen et al., 2015). The Nassari- Vienna (Austria). idae of Assemblage III were revised in Van Dingenen et FVD Frank Van Dingenen private collection, Brecht al. (2015), although a summary and update are included (Belgium). herein. LC Luc Ceulemans private collection, Rixensart In his unpublished thesis, Brébion (1964) of the Centre (Belgium). National de la Recherche Scientifique, Paris recorded 20 species within the groups covered in this paper from Le Pigeon Blanc and other Assemblage III localities, some Systematic palaeontology of which were described as new. However, as the thesis was never published, the names do not comply with ar- Order Neogastropoda Wenz, 1938 ticle 13 of the ICZN code (1999) and must be considered Superfamily Buccinoidea Rafinesque, 1815 nomina nuda. Family Buccinidae Rafinesque, 1815 Genus Aplus de Gregorio, 1885 Type species (by subsequent designation; Vokes, 1971) – Murex plicatus forma serzus de Gregorio, 1885, Neo- * For nr 3 in this series see Vita Malacologica 15: 35-55. gene, Italy. 24 Van Dingenen, Ceulemans & Landau. The lower Pliocene gastropods of Le Pigeon Blanc, 4. Neogastropoda (in part) 1826 Anna Risso, p. 214. Type species (by monotypy): siderable variability in the shell profile seen in the series Anna massena Risso, 1826, Pleistocene, France. illustrated here, with broader and more slender speci- Anna massena Risso, 1826 is a nomen dubium mens present. For comparison with congeners see Bru- (see Brunetti & Della Bella, 2014). netti & Della Bella (2014). 1885 Aplus de Gregorio, p. 279. Brébion (1964, p. 429) noted that Fusus scaber Mil- let was a synonym of A. inaequicostatus. He probably Note – Brunetti & Della Bella (2014) argued that Anna did not use Millet’s name, correctly considering Fusus massena Risso, 1826, is a nomen dubium, possibly a scaber Millet, 1854 to be a nomen nudum. However, species of Raphitoma (family Raphitomidae), and so the the name was later validated by the following descrip- genus Anna could not be used. The next available ge- tion: ‘Fusus scaber, Millet. Coq. petite, un peu allongée, neric taxon for this group of shells is Aplus de Gregorio, ventrue inférieurement; composée de six à sept tours 1885. De Gregorio (1885) did not designate a type spe- de spire garnis de côtes étroites, saillantes qui se ren- cies and included in his new genus Aplus, Murex plica- dent ainsi jusqu’à la suture; ces côtes sont couvertes tus ‘Brocchi’ (i.e., Murex plicatus Gmelin, 1791, sensu de stries serrées, rudes, si ce n’est la partie supérieure Brocchi, 1814). Although Brunetti & Della Bella (2014) de chaque tour qui n’en présente aucune. Ouverture designated Murex plicatus forma nilus de Gregorio, presque ovale, à canal très-court, et quelques légers 1885 as the type species, the type species of Aplus had plis se font remarquer sur la partie intérieure du bord already been designated by Vokes (1971, p. 83). droit, qui présente en dehors un fort bourrelet. Lon- WoRMS (Bouchet, 2015a) synonymised Aplus with Pol- gueur: 10-11 millimètres; diamètre: 4-5 millimètres. lia (type species: Buccinum undosum Linnaeus, 1758). Sc, Th. (1865, p. 591)’. We cannot apply Article 23.9.1.2 Pollia undosa is an Indo-Pacific species with quite a dif- (ICZN 1999) to consider Millet’s name a nomen obli- ferent shell form and unlikely to be monophyletic with tum as Couffon (1907, p. 185) used the name as a valid the eastern Atlantic group here ascribed to Aplus. Simi- taxon. Therefore, A. inaequicostatus (Bellardi, 1873) is larly, the tropical American ‘Anna’ species also form a a junior subjective synonym of Aplus scaber (Millet, distinct group, Ameranna Landau & Vermeij, 2012. Until 1865). molecular data proves otherwise, we prefer to keep them Millet (1865, p. 591) recorded this species from Assem- distinct. blage I localities of Sceaux d’Anjou and Thorigné, Bré- bion (1964, p. 428) added St-Michel. Brébion also recor- ded Cantharus (Pollia) exsculpta Dujardin, 1837 from Le Aplus scaber (Millet, 1865) Pigeon Blanc. We have not found any specimens of Aplus Plate 1, figs 1-3 exsculptus at Le Pigeon Blanc, and the record probably refers to A. inaequicostatus. 1854 Fusus Scaber Millet, p. 162 (nomen nudum). 1865 Fusus scaber Millet, p. 591. Distribution – Upper Miocene (Tortonian): Atlantic, NW 1873 Pollia aequicostata Bellardi, p. 182, pl. 12, fig. 23. France (Millet, 1865; Brébion, 1964). Lower Pliocene: 1907 Fusus scaber Millet – Couffon, p. 185. Atlantic, NW France (Brébion, 1964). Upper Pliocene: 1964 Cantharus (Pollia) exsculpta Dujardin, 1837 – Italy (Brunetti & Della Bella, 2014). Brébion (partim), p. 428 [non Aplus exsculptus (Dujardin, 1837)]. 1964 Cantharus (Pollia) aequicostata Bellardi, 1872 Genus Euthria Gray, 1850 [sic] – Brébion, p. 429, pl. 10, figs 24, 25. 1981 Pollia aequicostata Bellardi, 1872 [sic] – Ferrero- Type species (by subsequent designation; Petit, 2012) – Mortara et al., p. 48, pl. 6, fig. 8. Murex corneus Linnaeus, 1758, present-day, Mediterra- 2014 Aplus aequicostatus (Bellardi, 1877) – Brunetti & nean. Della Bella, p. 18, figs 5A-F. 1850 Euthria Gray, p. 67 Material and dimensions – Maximum height 14.6 mm. NHMW 2015/0133/0369-71 (3: Pl. 1, figs 1-3 respective- Note – Hadorn & Fraussen (1999) synonymised Sipho- ly), NHMW 2015/0133/0372 (32), LC (40), FVD (35). Le nofusus Drivas & Jay 1990 with Euthria Gray, 1850. Pigeon Blanc, Le Landreau, Nantes area, Loire-Atlan- Siphonofusus species are slender, with a longer sipho- tique department, NW France. nal canal than usual for Euthria and live in deep water. Moreover, they are from Japan and unlikely to be mono- Discussion – Brunetti & Della Bella (2014) reviewed the phyletic with Euthria, as envisaged here, which seems to Italian Pliocene Aplus species. The size, shape, sculpture be a European group. We are unconvinced that any of the and protoconch character of the Le Pigeon Blanc speci- Indo-Pacific species described i.e( . Fraussen & Hadorn, mens are most like that of Aplus aequicostatus (Bellardi, 2003) are monophyletic with the eastern Atlantic species. 1873). The protoconch of the French material consists of We therefore provisionally exclude Siphonofusus from about 2.5 convex whorls, with a medium-sized nucleus. the generic synonymy until we have more molecular data The protoconch shape is a little variable, inflated and so- on the group. mewhat uncoiled in some specimens. There is also con- Cainozoic Research, 17(1), pp. 23-61, June 2017 25 Euthria palumbina nov. sp. callus thin, adherent, sharply delimited, poorly expand- Plate 1, figs 4-6 ed. Siphonal fasciole rounded, narrow. 1964 Buccinulum (Euthria) lecointrei Brébion, p. 420, Discussion – Euthria palumbina nov. sp. is fairly typical pl. 10, figs 15-16 (nomen nudum). for the genus as understood here (see note under generic assignment above), although rather small shelled com- Type material – Holotype NHMW 2015/0133/0363 (Pl. pared to some of its congeners. The species is common in 1, fig. 4), height 38.6 mm; paratype 1 NHMW 2015/ the Le Pigeon Blanc assemblage and there is little vari- 0133/0364 (Pl. 1, fig. 5), height 25.8 mm; paratype 2 ability. Euthria adunca (Bronn, 1831) from the Pliocene NHMW 2015/0133/0366, height 24.0 mm (Pl. 1, fig. 6); Mediterranean is larger shelled, the shoulder is slightly paratype 3 MNHN.F.A57934, height 24.2 mm; para- more angular, the axial ribs are wider, the spiral cords type 4 MNHN.F.A57935, height 21.7 mm; paratype 5 stronger and the siphonal canal is longer. Euthria sub- MNHN.F.A57935, height 22.6 mm. marginata (d’Orbigny, 1852) from the middle Miocene of the Loire Basin is even smaller, squatter, thinner shelled, Other material – Maximum height 39.2 mm.