Tomellana sp.

Sacchetti, Claudia, Landau, Bernard & Ávila, Sérgio P., 2023, The Lower Pliocene marine gastropods of Santa Maria Island, Azores: Taxonomy and palaeobiogeographic implications, Zootaxa 5295 (1), pp. 1-150 : 84-85

Tomellana sp.

Plate 6 B

Santa Maria material examined. Maximum height 25.0 mm (apical fragment). One specimen from LNEG collection (unnumbered), Ponta do Norte lighthouse, Santa Maria Island, Touril Complex, Lower Pliocene.

Description. Spire fragment consisting of about six whorls (apical whorl obscured by matrix). Intermediate whorls with broad, swollen, subsutural collar, straight sided below, periphery at adapical suture, sculpture of very fine, weak spiral cords covering entire surface.

Discussion. Although represented by a spire fragment, with the apex covered with matrix, the barrel-shape spire whorls with a strongly developed subsutural collar and lack of axial sculpture, allows identification as a clavatulid of the Perrona -like species groups. Harzhauser et al. (2022: 102) restricted the use of the genus Perrona Schumacher, 1817 to species with comma-shaped axial riblets below the subsutural cords on the neanic spire whorls. Landau & Harzhauser (2022) placed the Pliocene Atlantic and Mediterranean species previously ascribed to Perrona into the genus Tomellana Wenz, 1943 , which do not have riblets on the neanic whorls. Although the Azorean specimen has the apex partially obscured by matrix, it is likely to be a Tomellana species and might represent T. onubensis Landau & Harzhauser, 2022 described from the Lower Pliocene Atlantic Guadalquivir Basin of Southern Spain. Unfortunately, the preservation does not allow us to confirm this identification. Harzhauser et al. (2022) traced the origin of the genus Tomellana to the Atlantic Aquitanian Lower Miocene of France, represented by T. jouannettii ( Desmoulins, 1842) . In the Pliocene it is represented mainly along the southern European Atlantic Frontage, with rare occurrences in the western and central Mediterranean ( Landau & Harzhauser, 2022). Today, the genus is restricted to Tropical West African waters.

Distribution. Lower Pliocene: Atlantic, Santa Maria Island, Azores (this paper).

Figures

PLATE 6. A1-A2. Conus s.l. sp. A, DBUA-F 1292-1, height 19.0 mm, diameter 13.0 mm, Ponta dos Frades. B. Tomellana sp., height 25.0 mm (apical fragment), Ponta do Norte lighthouse, LNEG collection (unnumbered). C, D. Crassopleura maravignae (Bivona, 1838), height 12.0 mm, width 4.5 mm, Pinheiros (figure C taken from Bronn in Reiss, pl. 1, fig. 9 and figure D taken from Mayer, 1864, pl. 6, fig. 50). E1-E2. Psilaxis simplex (Bronn, 1831), DBUA-F 828-3 height 1.5 mm, width 4.5 mm, Ponta dos Frades. F. Mathilda quadricarinata (Brocchi, 1814), DBUA-F 1023-2, height 1.9 mm, width 1.1 mm, Ponta do Castelo. G1-G2. Acteon semistriatus (Férussac, 1822), DBUA-F 191-9, height 7.3 mm width 3.9 mm, Malbusca. H1-H2. Cylichna sp., DBUA-F 1034-1, height 10.0 mm, width 5.0 mm, Macela viewpoint. I1-I3. Roxania utriculus (Brocchi, 1814), DBUA-F 1027-2, height 8.2 mm, width 4.5 mm, Malbusca II. J1-J2. Scaphander lignarius (Linnaeus, 1758), height 27.0 mm, width 15.5 mm, unknown locality, LNEG collection (unnumbered). K1-K2. Pyrgostylus cf. abreui (Peñas & Rolán, 2000), DBUA-F 471-2, height 6.0 mm, width 3.0 mm, Ponta do Castelo. L1-L3. Clathrella clathrata (Philippi, 1844), DBUA-F 471-1, height 6.0 mm, width 7.0 mm, Ponta do Castelo. M, N. Ranella bicoronata Bronn, 1862 species inquirenda, height 19.0 mm, width 15.0 mm, Pinheiros (figure M taken from Bronn in Reiss, 1862, pl. 1, fig. 8 and figure N taken from Mayer, 1864, pl. 7, fig. 53).