Pseudomalaxis zanclaeus ( Philippi, 1844 )

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 : 71

Pseudomalaxis zanclaeus ( Philippi, 1844)

Fig. 16 g–h

Bifrontia zanclaea Philippi, 1844 (p. 225, pl. 28, fig. 11).

Homalaxis nobilis Verrill, 1885 (p. 423, pl. 44, fig, 12).

Homalaxis zanclaeus Philippi—Jeffreys 1885 (p. 39).

Pseudomalaxis zanclaea (Philippi) — Monterosato 1913 (p. 362); Nordsieck 1968 (p. 64, pl. 10, fig. 37.20).

Pseudomalaxis actoni Monterosato 1913 (p. 362, upper fig. in p. 363).

Omalaxis zanclaeus — Hidalgo 1917 (p. 521).

Pseudomalaxis zanclaea ( Philippi, 1844) — Nordsieck 1972 (p. 147, pl. R XIV, fig. 7).

Pseudomalaxis zanclaeus ( Philippi, 1844) —Melone & Taviani 1984 (p. 181, figs. 53–59, 61).

Pseudomalaxis zancleus Philippi, 1844 — Rindone 1986 (p. 299, fig. 1).

Pseudomalaxis zanclea ( Philippi, 1844) — Barash & Danin 1992 (p. 68, fig. 64).

Pseudomalaxis zanclaeus meridionalis (Hedley, 1903) — Bieler 1993 (p. 315, figs. 262–265).

Pseudomalaxis zancleus ( Philippi, 1844) — Repetto et al. 2005 (p. 225, bottom right fig.); De Frias Martins et al. 2009 (p. 65, fig. 255).

Diagnostic characters. Nearly planispiral shell; orthocline quadrangular aperture; 4 spiral keels running along the angulations of the quadrangular whorls; stronger spiral duplicate and marking the periphery; weak spiral threads between the peripheral and the basal keel; fine sinuous axials; small nodes at the intersections of axials and spirals. Protoconch: not available (apical area worn); apparently smooth, of 2 whorls.

Remarks. Pseudomalaxis actoni Monterosato, 1913 and the Caribbean P. nobilis ( Verrill, 1885) are regarded as synonyms of P. zanclaeus (Melone & Taviani 1984; WoRMS 2016).

Occurrence. Box-corer sample BC72 (1 specimen). Diameter: 17 mm.

Distribution and habitat. Pseudomalaxis zanclaeus is widely distributed on both sides of the Atlantic and in the Mediterranean (typical form), as well as in the Indopacific area (subspecies meridionalis); it usually dwells on muddy bottoms (sometimes on sand and gravel) from circalittoral to bathyal depths, often in association with corals ( Monterosato 1913; Melone & Taviani 1984; Bieler 1993).

Fossil record. Pliocene of central and southern Italy; Pleistocene of southern Italy (Melone & Taviani 1984; Di Geronimo & La Perna 1997; Di Geronimo et al. 2005).

Figures

FIGURE 16. a – c: Pleurotomella gibbera Bouchet & Warén, 1980, sample BC 66, scale bars: 1 mm (a), 0.2 mm (b – c, protoconch); d – f: Discotectonica discus (Philippi, 1844), sample BC 72, scale bars: 2 mm (d – e), 0.2 mm (f, protoconch); g – h: Pseudomalaxis zanclaeus (Philippi, 1844), sample BC 72, scale bar 5 mm; i – k: Solatisonax alleryi (Seguenza, 1876), sample BC 72, scale bars: 2 mm (i – j), 0.2 mm (k, protoconch); l – n: Solatisonax bannocki (Melone & Taviani, 1980), sample BC 71, scale bars: 2 mm (l – m), 0.2 mm (n, protoconch); o – q: Spirolaxis centrifugus (Monterosato, 1890), sample BC 72, scale bars: 1 mm (o – p), 0.2 mm (q, protoconch).