Lamellaxis cf. gracilis (Hutton, 1834)

Simone, Luiz Ricardo L. & Casati, Rafael, 2013, New land mollusk fauna from Serra da Capivara, Piauí, Brazil, with a new genus and five new species (Gastropoda: Orthalicoidea, Streptaxidae, Subulinidae), Zootaxa 3683 (2), pp. 145-158 : 156

Lamellaxis cf. gracilis (Hutton, 1834)

( Figs. 49–50 )

Remarks. Lamellaxis gracilis is an extraordinarily wide-ranging species, occurring from Central America and the Caribbean Islands to tropical and subtropical South America ( Simone, 2006, and references therein). Except for antropic transportation, which has not been proved, the unusual widespread occurrence is difficult to explained. As some samples collected in the same place of remaining new described species are somewhat similar to L. gracilis , and as these subulinids still lack a comprehensive taxonomic revision, a conservative approach is given here identifying provisionally them as that species until further studies. The somewhat pointed protoconch is typical from this species, differing it from remaining Brazilian congeners. However, the Serra da Capivara specimens ( Figs. 49–50 ) are slightly more elongated, and further uniformly sculptured than the normal fashion of the species ( Simone, 2006: 184, fig. 669).

Measurements (in mm). MZSP 112406: 7.1 by 2.6; MZSP 112354: 8.6 by 2.5.

Material examined. BRAZIL. Piauí; Serra da Capivara ; Coronel José Dias municipality, close to Sítio do Mocó town, Cave Toca de Cima dos Pilão, 8°51’47.10”S 42°33’26.96”W, MZSP 112349, 3 shells, MZSP 112354, 3 shells ( Fig. 50 ), MZSP 112358, 1 shell, MZSP 112397, 1 shell, MZSP 112406, 1 shell ( Fig. 49 ), MZSP 112416, 2 shells (R. Casati col, 2012).

Figures

FIGURES 46 – 54. Shells. Figs. 46 – 48: Streptartemon molaris n. sp.; Fig. 46, paratype MZSP 111843 (W 7.6 mm), apertural view; Fig. 47, same, detail of aperture in slightly inferior view; Fig. 48, paratype MZSP 112366, young specimen (W 6.1 mm), apertural view; Fig. 49, Lamellaxis cf. gracilis, MZSP 112406, apertural view (L 7.1 mm); Fig. 50, same species, MZSP 112354, apertural view (L 8.6 mm); Figs. 50 – 54, Beckianum beckianum; Fig. 51, MZSP 112411 (L 6.5 mm), apertural view; Fig. 52, same, right view; Fig. 53, same, dorsal view; Fig. 54, MZSP 111542 (L 4.8 mm), apertural view; Fig. 55, dorsal view.