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Genus Aquitanobursa n. gen. TYPE SPECIES. — Ranella grateloupi d’Orbigny, 1852. DERIVATIO NOMINIS. — Derived from Aquitaine (Aquitania in Latin), the region where most of the species of the genus occur. SPECIES INCLUDED. — Aquitanobursa grateloupi (d’Orbigny, 1852) n. comb., Aq. amphitrites (Maury, 1917), n. comb., Aq. inaequicrenata (Cossmann & Peyrot, 1924) n. comb., Aq. morrisi (d’Archiac & Haimes, 1853) n. comb., Aq. tuberosa (Grateloup, 1833) n. comb. DIAGNOSIS. — Shell thick, moderately short-spired, varices slightly displaced, 6 primary cords on the convex part of the whorl, variceal and intervariceal P2 very reduced, axial ridges on the first whorl, parietal callus prominent. Posterior siphonal canal short, well-defined; outer lip with weak projection. COMPARISON. — With their deeply marked and angular varices and strongly expressed shoulder, Aquitanobursa n. gen. species resemble some deep-sea species of the Bursa s.l. genus such as Bursa quirihorai Beu, 1987 (Fig. 3H); however, Aquitanobursa n. gen. species are much strongly built, with a thicker shell. Atavistic features displayed by deep-sea gastropods are a well-known phenomenon, described recently for Muricidae by Merle (2012). The phylogenetic relationships of Aquitanobursa n. gen. with other Bursidae remain unclear; this genus is possibly a sister group to all Recent Bursidae, but that in unlikely considering that it occurs at the same time as Aspa marginata and Bursa corrugata. A fair assumption would be that it is the sister group to all bursids except Aspa and B. corrugata, but that would need a phylogenetic analysis for confirmation. Aquitanobursa grateloupi (d’Orbigny, 1852) n. comb. (Fig. 7A) Ranella gratteloupi [sic] d’Orbigny, 1852: 76. Ranella leucostoma – Grateloup 1833: 91, pl VI (not Lamarck, 1822). Ranella semigranosa – Grateloup 1845: pl. XXIX, fig. 6 (not Lamarck, 1822). urn:lsid:zoobank.org:act: 69CEE556-A552-4FB2-AE6A-2FCB4374C21D Apollon grateloupi – Cossmann & Peyrot 1924: 305, pl. XV, figs 42, 43. TYPE LOCALITY. — Lower Miocene of Aquitaine Basin, Bordeaux and Saint-Paul-lès-Dax, France. TYPE MATERIAL. — MNHN.F. A27211 (from Saint-Paullès-Dax) is here designated as lectotype. One paralectotype (MNHN.F. B27595). OTHER MATERIAL EXAMINED. — 13 specimens from Brongniart coll. from le Peloua, Burdigalian. GEOGRAPHIC AND STRATIGRAPHIC OCCURRENCE. — Bursa grateloupi is only known from the lower Miocene of the Aquitaine Basin. REMARKS Aquitanobursa grateloupi n. comb. was originally written gratteloupi. This name is obviously based on that of J.P.S. de Grateloup, and in accord with ICZN 32.5.1 the correct spelling is Aquitanobursa grateloupi n. comb. |
