Bolma cf. rugosa (Linné, 1767)

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 : 25

Bolma cf. rugosa (Linné, 1767)

Plate 1 C

cf. Turbo rugosus Linné 1767: 1234 .

Santa Maria material examined. Maximum diameter 4.1 mm. DBUA-F 471-3 (1), Ponta do Castelo, Santa Maria, Azores, Touril Complex, Lower Pliocene.

Discussion. Landau et al. (2013: 30) discussed the differences between members of the Bolma rugosa (Linné, 1767) species group from the Miocene and Pliocene, and showed that they were different species. For the Miocene form the name B. meynardi ( Michelotti, 1847) is available. The specimen from the Upper Miocene Tortonian of NW France recorded as B. cf. meynardi by Landau et al. (2017: 115, pl. 40, figs. 1-3) differ in having a lower spire, in having less nodulous rugae, in having the periphery of the last whorl between the shoulder and the basal carinae strongly concave, and in having the outer lip fused with the last whorl at the level of the basal carinae. The French Tortonian form will be described as new (Landau et al. in press).

The Azorean material consists of a single juvenile showing the flattened protoconch and earliest teleoconch whorl typical for the genus, and spinous shoulder with three rows of tubercles between the suture and the spinous shoulder. This could represent B. rugosa , but with the scant and immature material available, further identification is not possible.

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

Today, B. rugosa is not present in the Azores ( Ávila et al. 1998, 2000; Martins et al. 2009; Cordeiro et al. 2015), occurring in the Mediterranean Sea, Portugal, West African Atlantic shores, and the Macaronesian archipelagos of Madeira, Selvagens and Canary Islands.

Bolma ? mariae ( Mayer, 1864) species inquirenda

* Turbo Mariae Mayer 1864: 61 .

Type material. No dimension given, Feteirinhas (= Ponta das Salinas), Santa Maria Island , Azores; whereabouts unknown ( Beu 2017: 165).

Original description. “ Ein kleiner Deckel und die nur drei Windungen zählende Spitze einer Schale deuten auf eine kleine Art aus der Gruppe der T. rugosus , mamillariş und muricatus, und die diesem letzteren zunächststand, allein durch die der Kante statt der Naht genäherte K̂rnerreihe auf der oberen Fläche, durch das Fehlen aller K̂rnelung auf der unteren und durch die deutliche Querfalte auf beiden sich unterscheidet . [ A small operculum and the tip of a shell, which has only three whorls, indicate a small species from the group of T. rugosus , mamillaris , and muricatus, and that is closest to the latter one, solely through the margin instead of the row of granules close to the suture on the upper surface, because of both the absence of any granulation on the base and by the clear transverse fold].” ( Mayer 1864: 61).

Discussion. This species was described but not figured by Mayer (1864: 61). We have placed it in the genus Bolma Risso, 1826 , as the original description compares it to other Bolma species. The specimen is clearly juvenile at only three whorls. No material at hand fits the description.

Distribution. Lower Pliocene: Atlantic, Santa Maria Island, Azores ( Mayer 1864).

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.