Mathilda cochlaeformis Brugnone, 1873

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 : 74

Mathilda cochlaeformis Brugnone, 1873

Fig. 17 a–c

Trochus elegantissimus Costa, 1861 (p. 55, pl. 9, fig. 1).

Mathilda cochlaeformis Brugnone, 1873 (p. 5, fig. 1).

Mathilda granolirata Brugnone, 1873 (p. 6, fig. 2).

Mathilda elegantissima, Costa—Tryon 1886 (p. 210, pl. 64, figs. 17–18; pl. 65, fig. 36).

Mathilda elegantissima ( O.G. Costa, 1861) —Sabelli & Spada 1978[a] (p. 1, fig. 2).

Mathilda cochleaeformis [sic] Brugnone, 1873 — Barash & Danin 1992 (p. 68).

Mathilda cochlaeformis — Rocchini 2004 (p. 106, fig. 5).

Mathilda cochlaeformis Brugnone, 1873 — Repetto et al. 2005 (p. 226, mid left fig.); Beck et al. 2006 (p. 84, mid figure); Peñas et al. 2006 (figs. 290–292); Crocetta & Spanu 2008 (fig. 3G); De Frias Martins et al. 2009 (p. 65, fig. 256).

Diagnostic characters. Turreted shell; roundly angular teleoconch whorls; rounded aperture; three main spiral cords per whorl, the two abapical ones of nearly equal strenght; numerous thin axial riblets forming nodules at intersections with spiral cords; non-nodulose spirals on base. Protoconch: heterostrophic, transaxial, helicoidal; 2.75 whorls; diameter about 670 µm; surface smooth; transition to the teleoconch marked by a thin varix.

Remarks. Mathilda elegantissima ( Costa O. G., 1861) and M. granolirata Brugnone, 1873 are currently regarded as synonyms of M. cochlaeformis (fide CLEMAM 2016). Trochus elegantissimus Costa O. G., 1861 has no priority because it is a homonym predated by T. elegantissimus d’Orbigny, 1852 , a middle Miocene fossil taxon.

Occurrence. Box-corer samples BC22 (1 specimen), BC66 (1), BC68 (1), BC71 (4), BC72 (1); core BC51 (2). Maximum height: 8.5 mm.

Distribution and habitat. Mathilda cochlaeformis is distributed in the Mediterranean and the eastern Atlantic (from the Lusitanian province to Madeira, the Canaries and St. Helena), on circalittoral to bathyal sand ( Poppe & Goto 1991; Barash & Danin 1992; Beck et al. 2006; De Frias Martins et al. 2009). It was also found associated with a Sardinian deep water population of Corallium rubrum ( Crocetta & Spanu 2008) .

Fossil record. None recorded.

Figures

FIGURE 17. a – c: Mathilda cochlaeformis Brugnone, 1873, samples BC 71 (a) and BC 66 (b – c), scale bars: 2 mm (a), 0.2 mm (b – c, protoconch); d – g: Mathilda coronata Monterosato, 1875, sample BC 71, scale bars: 2 mm (d), 0.2 mm (e – g, protoconch); h – j: Eulimella scillae (Scacchi, 1835), sample BC 72, scale bars: 1 mm (h), 0.2 mm (i – j, protoconch); k – m: Eulimella unifasciata (Forbes, 1844), sample BC 72, scale bars: 2 mm (k), 0.2 mm (l – m, protoconch); n – o: Chrysallida flexuosa (Monterosato, 1874), sample BC 67, scale bars: 0.5 mm (n), 0.2 mm (o, protoconch); p – r: Liostomia sp., sample BC 72, scale bars: 1 mm (p), 0.2 mm (q – r, protoconch).