Ennucula aegeensis ( Forbes, 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 : 15

Ennucula aegeensis ( Forbes, 1844)

Fig. 2 c–e

Nucula aegeensis Forbes, 1844 (p. 192).

Nucula aegeensis Forbes—Jeffreys 1879 (p. 581).

Lionucula tenuis aegeensis ( Forbes, 1843) — Nordsieck 1969 (p. 3, pl. 1, fig. 00.02).

Nucula tenuis aegeensis (Forbes) — Di Geronimo & Panetta 1973 (p. 92, pl. 3, fig. 2).

Nucula (Leionucula) tenuis aegeensis Forbes—Di Geronimo 1974 (p. 153, pl. 5, figs. 1,4).

Nuculoma aegeensis Forbes, 1844 — Cossignani et al. 1992 (fig. 256).

Nucula aegeensis Forbes, 1844 — Poppe & Goto 1993 (p. 38, pl. 1, fig. 19).

Ennucula aegeensis ( Forbes, 1844) — Salas 1996 (p. 38, figs. 16–18); La Perna 2003 (p. 23, pl. 1, fig. 3); Repetto et al. 2005 (p. 282, mid left fig.); Mastrototaro et al. 2010 (fig. 5 k).

Ennucula aegensis [sic] ( Forbes, 1844)— Giannuzzi-Savelli et al. 2001 (p. 48, figs. 26–28).

Ennucula aegeensis (Forbes) —Rosso et al. 2010 (fig. 11 D).

Diagnostic characters. Suboval outline; inner ventral margin not crenulated; low weak commarginal cords, more evident on later growth stages. Prodissoconch: shell type ST-1B; P-1: length about 290 µm; ellipsoidal outline; convex, slightly asymmetrical profile; smooth surface except for the cicatrix area; transition to the nepioconch well marked.

Occurrence. Box-corer samples BC04 (7 specimens), BC05 (5), BC11 (1), BC66 (5), BC71 (5), BC72 (94); cores BC04 (4), BC05 (22), BC21 (33), BC51 (33), BC67 (1), BC72 (30). Maximum length: 5 mm.

Distribution and habitat. Ennucula aegeensis is an almost exclusively Mediterranean species, with some citations from the Lusitanian province; it occurs on mud and coral debris from the circalittoral zone to over 2800 m depth ( Nordsieck 1969; Poppe & Goto 1993; Pons-Moyà & Pons 1999). It was regarded as an exclusive characteristic taxon of VP (bathyal mud) biocoenosis (Di Geronimo 1979[a]; Di Geronimo et al. 1982) and characterizes the Abra-Nucula biocoenosis in the bathyal of Taranto ( Di Geronimo & Panetta 1973). In the Santa Maria di Leuca CWC biotope, it was found on the muddy bottoms around the coral colonies (Mastrototaro et al. 2010), being abundant in mollusk mud, and common in coral rubble and foraminifer mud thanatofacies (Rosso et al. 2010).

Fossil record. Pliocene of Italy ( Tabanelli 2008); probably also Pleistocene of the Mediterranean ( La Perna 2003).

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).