Pristigloma minima ( Seguenza, 1877 )

Negri, Mauro Pietro & Corselli, Cesare, 2016, Bathyal Mollusca from the cold-water coral biotope of Santa Maria di Leuca (Apulian margin, southern Italy), Zootaxa 4186 (1), pp. 1-97 : 15-16

Pristigloma minima ( Seguenza, 1877)

Fig. 2 l–n

Yoldia minima Seguenza, 1877 (p. 1178, pl. 5, fig. 17).

Leda minima Seguenza—Jeffreys 1879 (p. 581).

Pristigloma (?) minima (Seguenza, 1873/77)— Nordsieck 1969 (p. 6, pl. 1, fig. 01.14). Yoldia minima Seguenza—Di Geronimo & Li Gioi 1980 (pl. 2, figs. 1–2).

“ Yoldia ” minima ( Seguenza, 1877) —Di Geronimo & La Perna 1997 (p. 412, pl. 7, figs. 1–2, 10–12). “ Yoldia ” minima Seguenza, 1877 — La Perna 2003 (p. 24, pl. 3, figs. 14–15). Pristigloma minima ( Seguenza G., 1877) — Repetto et al. 2005 (p. 282, bottom right fig). Yoldia minima Seguenza G., 1877 — Beck et al. 2006 (p. 94, mid fig.).

Diagnostic characters. Oval outline; markedly opisthogyrous beaks; gently arched anterior hinge; outer surface with uneven growth markings. Prodissoconch: shell type ST-1A; P-1: length about 140 µm; inequilateral (anterior side longer), ellipsoidal outline; convex profile; surface with irregular to commarginal wrinkles; transition to the nepioconch weakly marked.

Remarks. WoRMS (2016) considers the family name Pristiglomidae as a synonym of Sareptidae Stoliczka, 1870 . Although no live specimens were recovered, the freshness of the shells at hand (preservation code 4 sensu Basso & Corselli (2007) i.e., with traces of ligament) suggests the occurrence of this species among the Recent Mediterranean molluskan fauna—a hitherto debated question ( La Perna 2003).

Occurrence. Box-corer samples BC66 (1 specimen), BC67 (3), BC72 (4); cores BC04 (2), BC67 (7), BC72 (9). Maximum length: 2 mm.

Distribution and habitat. Pristigloma minima is a northern Atlantic to Mediterranean species, found in the 20–2664 m depth interval—including seamounts—but more typical of bathyal deeper horizons ( Nordsieck 1969; Di Geronimo & La Perna 1997; Di Geronimo et al. 2005; Beck et al. 2006).

Fossil record. Common taxon in Pliocene and Pleistocene bathyal deposits of Italy ( Seguenza 1877; Di Geronimo & Li Gioi 1980; Di Geronimo & Bellagamba 1985; Di Geronimo & La Perna 1997; La Perna 2003; Di Geronimo et al. 2005).

Figures

FIGURE 2. a – b: Nucula sulcata Bronn, 1831; RV, sample BC 06, scale bar: 5 mm; c – e: Ennucula aegeensis (Forbes, 1844); RV (c, e) and LV (d), sample BC 72, scale bars: 1 mm (c – d), 0.1 mm (e, prodissoconch); f – h: Ledella messanensis (Jeffreys, 1870); LV, sample BC 72, scale bars: 1 mm (f – g), 0.1 mm (h, prodissoconch); i – k: Malletia obtusa (Sars M. in Sars G. O., 1872); RV (j, k) and LV (i), samples BC 72 (i) and BC 71 (j – k), scale bars: 2 mm (i – j), 0.1 mm (k, prodissoconch); l – n: Pristigloma minima (Seguenza, 1877); RV (m) and LV (l, n), sample BC 72, scale bars: 0.5 mm (l – m), 0.1 mm (n, prodissoconch); o – q: Yoldiella lucida (Lovén, 1846); RV, sample BC 72, scale bars: 1 mm (o – p), 0.1 mm (q, prodissoconch).