Gibberula vignali Dautzenberg & Fischer, 1896

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 : 64-65

Gibberula vignali Dautzenberg & Fischer, 1896

Plate 4 G 1 -G 3

* Gibberula vignali Dautzenberg & Fischer 1896: 433 , pl. 15, fig. 17.

? Gibberula lazaroi Contreras 1992: 44 , 45, unnumbered fig.

Gibberula vignali ( Dautzenberg & Fischer, 1896) — Martins 2009: 64, fig. 198.

Santa Maria material examined. Maximum height 2.8 mm, width 1.6 mm. DBUA-F 1044-1 (1), Pedra-que-pica, Santa Maria Island, Azores, Touril Complex, Lower Pliocene.

Description. Shell small for genus, solid, cylindrical-ovate, with low spire. Protoconch covered by callus. Teleoconch of about two whorls, suture superficial. Last whorl more than 95% total height, convex, maximum diameter situated just above mid-height, not constricted at base. Surface smooth and glossy. Aperture narrow, elongate, weakly curved, slightly wider abapically. Outer lip moderately thickened, not extending adapically to level of suture, abapically extending just beyond tip of siphonal fasciole, smooth within; siphonal canal very short, open, shallowly notched. Columella weakly convex, bearing about six plications on the lowe half, the adapical two subobsolete, abapical four plications more strongly developed, strengthening abapically. Two abapical plications extend externally over columella. Parietal callus weakly developed, narrowly expanded over venter. Siphonal fasciole not delimited.

Discussion. Gibberula vignali ( Dautzenberg & Fischer, 1896) , is characterised by small sized shells for the genus, low spire, outer lip that slopes steeply downwards from the point of insertion, and is not alate adapically, the inner lip bearing small, weak denticles and columella seven folds, increasing in strength abapically. The last two folds do not extent over the venter as they do in some of its congeners. Contreras (1992) described G. lazaroi from present-day Pico and Terceira Islands, Azores. In his discussion he did not compare his new taxon to G. vignali . Comparing the illustration of the holotype ( Contreras 1992: 45, unnumbered figure) with that of G. vignali ( Dautzenberg & Fischer 1896: pl. 15, fig. 17) we fail to see any significant differences between the two, which are both 2.0 mm in height. On the WoRMs database is a photograph of a specimen identified as G. vignali from Morocco. This specimen is squatter with a more alate outer lip and fewer columellar folds than the holotype, and we are unsure if it represents the same species. We have not seen the holotypes of these two species and therefore refrain from synonymising them.

Several small, eastern Atlantic Gibberula species need to be compared. Gibberula lazaroi is closely similar to G. jansseni Van Aartsen, Menkhorst & Gittenberger, 1984 , from the Bay of Algeciras, Spain, but differs in being slightly more globose and having more numerous columellar folds, which are coarser. Gibberula hernandezi Contreras & Talavera, 1988 , from the Madeira, Selvagens and the Canary Islands, is immediately separated by a taller spire with two sutures visible and the anterior columellar folds that extend over the venter.

Gibberula vignali , together with Alvania mediolittoralis Gofas, 1989 , and A. sleursi ( Amati, 1987) form part of the endemic Azorean fauna that was already present in the early Pliocene.

Distribution. Lower Pliocene: Atlantic, Santa Maria Island, Azores (this paper). Present-day: Atlantic, Azores ( Dautzenberg & Fischer 1896;? Contreras 1992; Martins et al. 2009).

Figures

PLATE 1. A. Danilia pterostomus (Bronn, 1861), height 5.0 mm, width 4.0 mm, Forno da Cré (figure taken from Bronn in Hartung, 1861, pl. 19, fig. 2). B1-B2. Emarginula octaviana Coen, 1939, DBUA-F 487-1, height 1.8 mm, diameter 3.0 mm, Ponta do Castelo. C. Bolma cf. rugosa (Linné, 1767), DBUA-F 471-3, diameter 4.1 mm, Ponta do Castelo. D1-D5. Turbo hartungi Bronn 1861, DBUA-F 1295-1, height 9.0 mm, width 8.0 mm, Malbusca (east cave). E1-E3. Nerita cf. funata Dujardin, 1837, DBUA-F 917-1, height 4.0 mm, width 6.0 mm, Ponta do Castelo. F1-F2. Thericium crenulosum (Bronn, 1862), height 10.0 mm, width 6.0 mm, Ponta do Norte lighthouse, LNEG collection (unnumbered). G1-G2. Thericium hartungi (Mayer, 1862), height 29.0 mm, width 13.0 mm, Pinheiros (figure taken from Bronn in Reiss, 1862, pl. 1, fig. 11). H1-H2. Thericium incultum (Mayer, 1862), DBUA-F 1034-2, height 23.0 mm, width 10.0 mm, Macela viewpoint. I1-I2. Thericium incultum (Mayer, 1862), DBUA-F 1027-1, height 29.0 mm, width 11.0 mm, Malbusca II. J1-J2, K1-K2. Bittium miradouroense nov. sp., Holotype DBUAF 1034-5, height 6.8 mm, width 1.9 mm (J); Paratype DBUA-F 1034-6(1), height 5.3 mm, width 1.9 mm (K), Macela viewpoint. L1-L2, M1-M2. Bittium nov. sp., DBUA-F 488-2, height 4.5 mm, width 1.8 mm (L), height 4.2 mm, width 1.7 mm (M), Ponta do Castelo.

PLATE 3. A. A1-A2. Alvania mediolittoralis Gofas, 1989, DBUA-F 962-2, height 2.1 mm, width 1.2 mm, Ponta do Castelo. B. Alvania sleursi (Amati, 1987), DBUA-F 471-4, height 2.0 mm, width 1.1 mm, Ponta do Castelo. C1-C2. Alvania sleursi (Amati, 1987), DBUA-F 962-3, height 3.2 mm, width 1.8 mm, Ponta do Castelo. D1-D3. Rissoina pusilla (Brocchi, 1814), DBUA-F 488-1, height 5.2 mm, width 2.1 mm, Ponta do Castelo. E1-E3. Macromphalina depressa (Boettger, 1907), DBUA-F 1023-3, height height 1.0 mm, width 1.8 mm, Ponta do Castelo. F. Calyptraea chinensis (Linnaeus, 1758), DBUA-F 926-1, diameter 18.0 mm, Malbusca 2. G1-G2. Schilderia utriculata (Lamarck, 1810), height 24.0 mm, width 15.0 mm, unknown locality, LNEG collection (unnumbered). H1-H3. Erato mayeri nov. sp., Holotype DBUA-F 1189-C, height 7.7 mm, width 5.3 mm, Pedra-que-pica. I1-I3. Erato mayeri nov. sp., Paratype DBUA-F 1291-1, height 8.9 mm, width 6.0 mm, Ponta dos Frades. J1-J4. Pseudopusula parcicosta (Bronn, 1862), DBUA-F 469-1, height 9.0 mm, width 6.5 mm, Ponta do Castelo.

PLATE 4. A. Tethystrombus coronatus (Defrance, 1827), CIADP-F 32, height 119.1 mm, width 107.2 mm, Figueiral. B. Talisman scrobilator (Linnaeus, 1758), Ponta dos Cedros, size not known, LNEG collection (unnumbered, specimen not seen, part of a photograph database). C. Aspa marginata (Gmelin, 1791), DBUA-F 1428-1, height 28.0 mm, width 20.0 mm, Ponta dos Cedros. D1-D2. Monoplex comptus (A. Adams, 1855) height 25.0 mm, width 14.0 mm, Pinheiros (figure D1 taken from Bronn in Reiss, 1862, pl, 1, fig.10 and figure D2 from Mayer, 1864, pl. 7, fig. 52). E1-E3. Distorsio mcgintyi Emerson & Puffer, 1953, DBUA-F 1189-1, height 31.0 mm, width 18.0 mm, Pedra-que-pica. F. Xenophora sp., height 70.0 mm, diameter 15.0 mm, unknown locality, LNEG collection (unnumbered). G1-G3. Gibberula vignali Dautzenberg & Fischer, 1896, DBUA-F 1044-1, height 2.8 mm, width 1.6 mm, Pedra-que-pica. H1-H2. Cancellaria parcestriata Bronn, 1862, height 10.0 mm, width 6.5 mm, Pinheiros (figure H1 taken from Bronn in Reiss (1862), pl. 1, fig. 7 and figure H2 from Mayer (1864), pl. 7, fig. 51). I1-I2. Costoanachis semicostata (Sacco, 1890), DBUA-F 1034-4, height 6.9 mm, width 3.0 mm, Macela viewpoint. J. Costoanachis sp., DBUA-F 1059, height 2.7 mm, width 1.6 mm, Baía do Raposo. K. Angustifusus longiroster (Brocchi, 1814), height 36.0 mm, width 18.1 mm, unknown locality, LNEG collection (unnumbered). L. Fusinus nov. sp.?, height 51.0 mm, width 24.0 mm, Ponta do Norte lighthouse, LNEG collection (unnumbered).