Pleurotomella eurybrocha Dautzenberg & Fischer 1896

Pleurotomella eurybrocha (Dautzenberg & Fischer, 1896)

Fig. 15 j–l

Pleurotoma eurybrocha Dautzenberg & Fischer, 1896 (p. 427, pl. 15, fig. 14).

Pleurotomella (Gymnobela) eurybrocha (Dautzenberg & H. Fischer) — Nordsieck 1968 (p. 184, pl. 31, fig. 95.65). Pleurotomella (Gymnobela) eurybrocha (Dautzenberg & Fischer, 1896) — Nordsieck 1977 (p. 68, pl. 26, fig. 137). Pleurotomella eurybrocha (Dautzenberg & Fischer, 1896) — Bouchet & Warén 1980 (p. 39, figs. 92, 224–225). Pleurotomella eurybrocha (Dautzenberg and Fischer, 1896) — Poppe & Goto 1991 (p. 173, pl. I, fig. 30). Pleurotomella eurybrocha (Dautzenberg & Fischer H., 1896) — Repetto et al. 2005 (p. 215, top right fig.).

Diagnostic characters. Fusiform shell; oval aperture; moderately long and twisted siphonal canal; rather deep anal sinus; 11 collabral ribs per whorl crossed by spiral cordlets; short recurved spines at the intersections of ribs and cordlets; stronger spines bordering the subsutural shelf. Protoconch: conical; 3.5 whorls; diameter about 480 µm (protoconch I: 250 µm); height about 630 µm; first 1.5 whorls (protoconch I) with spirally connected T-shaped granules forming a square reticulated pattern; subsequent whorls (protoconch II) with sinuous, collabral, opisthocyrt axial riblets and non-collabral prosocline riblets; the latter riblets absent in the adapical third, where only collabral riblets are present; terminal spiral keel; transition to the teleoconch at sinusigera.

Remarks. A single juvenile specimen was at hand.

Occurrence. Core BC21 (1 specimen). Height: 2 mm.

Distribution and habitat. Pleurotomella eurybrocha ranges from the northeastern Atlantic to the Azores and the Mediterranean, being a soft bottom dweller at bathyal depths, occasionally found at lower settings in the Mediterranean (Panetta 1971; Nordsieck 1977; Bouchet & Warén 1980; Poppe & Goto 1991). It was regarded as a characteristic element of the VP (bathyal mud) biocoenosis (Di Geronimo et al. 1982).

Fossil record. Possibly Pleistocene of Sicily (Di Geronimo et al. 1982 as P. cf. eurybrocha).