Odostomella cf. doliolum ( Philippi, 1844 )

Pimenta, Alexandre Dias, Absalão, Ricardo Silva & Miyaji, Cintia, 2009, A taxonomic review of the genera Boonea, Chrysallida, Parthenina, Ivara, Fargoa, Mumiola, Odostomella and Trabecula (Gastropoda, Pyramidellidae, Odostomiinae) from Brazil, Zootaxa 2049, pp. 39-66 : 58-61

Odostomella cf. doliolum ( Philippi, 1844)

( Figs. 57−61 )

Types of Odostomella doliolum: According to Schander et al. (1999b), not given in original description (reported by author from Pleistocene of Taranto, Italy).

Type locality: Not known ( Schander et al. 1999b).

Material examined: --shells of Odostomella doliolum from Europe: -- Italy: IBUFRJ 11893, Dente del Diavolo, R. Calabria, Scilla, 42 m, 02/ii/1993, L. Giunchi leg. [5]; --Canary Islands: IBUFRJ 11892, Poris de Abona, 5 m, Tenerife, 16/viii/1989, R. Moolenbeek and Duiveman leg. [2]; IBUFRJ 11894, Tenerife, iv/1986, R. Moolenbeek and Duiveman leg. [2].

--shells of Odostomella cf. doliolum from Brazil: --southeast and south of Brazil: -- PADCT expedition: MZSP 86805, sta 6595 [20]; MZSP 86806, sta 6635 [4]; MZSP 86826, sta 6641 [2]; MZSP 86827, sta 6611 [1]; MZSP 86828, sta 6608 [3]; MZSP 86829, sta 6571 [2]; MNRJ 10955, sta 6606 [7]; MZSP 86830, sta 6631 [1]; MNRJ 10883, sta 6595 [5]. REVIZEE expedition: MZSP 86831, sta 6672 [1]; MZSP 86832, sta 6653 [10]; MZSP 86833, sta 6676 [1]; MZSP 86834, sta 6678 [1]; MZSP 86835, sta 6666 [1]; MZSP 86836, sta 6653 [1]; MNRJ 10884, sta 6669 [1]; MNRJ 10885, sta 6668 [1].

Remarks: Schander et al. (1999b) reviewed the taxonomy of the genus Odostomella . In previous works on the taxonomy of European Pyramidellidae , Odostomella was considered a subgenus of Chrysallida (e.g., Aartsen, 1977; Linden & Eikenboom 1992), until Schander (1994) demonstrated that both genera are quite different in protoconch and external anatomy. In this opinion he was followed by Odé (1993b), Penãs et al. (1996) and Schander et al. (1999a, 1999b).

The only two species of Odostomella from the western Atlantic are O. carceralis ( Fig. 49 ), from Brazil ( Pimenta et al., 2000), known only from type locality, and O. doliolum , recorded from the Gulf coast of Texas by Odé (1993b) as “ Odostomela cf. doliolum ” and “ Odostomella doliolum different morph”.

Herein, we list a third species, originally described by Jong and Coomans (1988) in the genus Turbonilla : Odostomella fonteini , new combination ( Figs. 52−55 ). The species has a protoconch very immersed into the first teleoconch whorls ( Fig. 55 ), with only one whorl, suggesting non-planktonic development, and axial sculpture and shell shape ( Figs. 52−54 ) very similar to the type species of Odostomella , where it is better allocated.

Odé (1993b) stated that O. fonteini is a synonym of O. doliolum . However, O. fonteini can be distinguished by its more pupoid shape, more intorted protoconch, homogeneous golden color with no spiral color bands, and axial ribs that continue through the umbilicus. This is the first report of this species from the southwestern Atlantic, where it has been collected off the northeast Brazilian coast. The species has also been reported from the Bahamas ( Redfern 2001), though in its original generic allocation.

The occurrence of Odostomella doliolum in the western Atlantic is somewhat dubious. This species is present in the Mediterranean and North African coasts ( Linden & Eikenboom, 1992; Schander, 1994; Peñas et al., 1996; Schander et al., 1999b). According to Odé (1993b), this species may have a worldwide distribution, since he considered that its many forms have been described by many authors from Europe and probably South Africa, Vietnam, the Red Sea and the Hawaiian Islands. Odé (1993b) also considered that among these taxa, there are only a few, or perhaps one species, including the taxon from the Gulf of Mexico that he determined as Odostomella cf. doliolum . Schander et al. (1999b), on the other hand, considered that the taxon reported by Odé (1993b) must represent a different species, since the record falls well outside the reported geographical range of O. doliolum .

Actually, Odé (1993b) reported two morphs of this species: the one named “ Odostomella cf. doliolum ”, described as having two spiral colored bands; and “ Odostomella doliolum different morph”, described as much smaller and uniformly golden-amber. Since Odé (1993b) provided no illustration of his material, we can only suspect that the material that he termed “ Odostomella cf. doliolum ” corresponds to the Brazilian material that we designate herein as Odostomella cf. doliolum , and his “different morph” corresponds to Odostomella fonteini , based on his description of a smaller, golden-brown species. As we demonstrated above, O. fonteini is indeed a distinct species.

The Brazilian specimens of Odostomella cf. doliolum ( Figs. 57−61 ) are very constant in shell shape and sculpture, and very similar to shells from Europe ( Fig. 56 ), as well to the figures of Odostomella doliolum in Linden and Eikenboom (1982), Schander (1994), Peñas et al. (1996) and Schander et al. (1999b). All specimens from Brazil have a single yellow spiral band on each whorl, and an additional band on the base of the last whorl. In the European specimens, as illustrated by Linden and Eikenboom (1992), shells can have this same color pattern, or they may have two spiral bands on each whorl, plus the additional band on the base (see for example, figs. 13, 14 in Linden & Eikenboom, 1992).

As stated above (considerations about geographic distribution), in the absence of a named taxon from the western Atlantic to which the Brazilian specimens could be related, we do not describe this material, and, for the present, we have decided to term them Odostomella cf. doliolum .

In Brazil, Odostomella cf. doliolum is restricted to localities in the southeast and south (≅ 24o S to 28o S).

Figures

FIGURE 51 – 61. 51. Odostomella carceralis (paratype, IBUFRJ 10848: whole shell, length: 2.95 mm). 52 − 55. Odostomella fonteini: 52: holotype (ZMA 3.87.111); 53 − 55 (IBUFRJ 8332): 52 − 53. whole shells (respective lengths: 1.4 mm; 1.2 mm); 54. last whorl; 55. protoconch. Scale bars: 200 Μm. 56. Odostomella doliolum (IBUFRJ 11893: whole shell, length: 3.0 mm). 57 − 61. Odostomella cf. doliolum. 57: (MNRJ 10883); 58 − 61: (MNRJ 10884). 57 − 58: whole shells (respective lengths: 57: 3.3 mm; 58: 3.2 mm); 59: last whorl; 60 − 61: protoconchs. Scale bars: 200 Μm.

FIGURES 48 − 50. Mumiola gradatula: 48: holotype of Rissoa toroensis (ANSP 211885); 49 − 50. (IBUFRJ 11155): 48 − 49. whole shells (respective lengths: 2.35 mm; 1.4 mm); 50. protoconch. Scale bars: 100 Μm.