Balanophyllia cellulosa Duncan 1873

Balanophyllia cellulosa Duncan, 1873

(Figs. 6 H–I, tables 1−3)

Balanophyllia cellulosa Duncan, 1873: 333, pl. 49, figs. 11–12.—Zibrowius 1980: 187, pl. 95, figs. A–L.—Monteiro Marques & Andrade 1981: 88.—Zibrowius 1985: 319, tab. 2.—Cairns & Chapman 2001: 34 (tab. 1).—Reveillaud et al. 2008: 322 (tab. 1), 325 (fig. 4).—Altuna 2010: 21.

Material examined. Le Danois Bank, 2008: Stn. D 6V, 555 m, a broken specimen of doubtful identification; Stn. S 7V, 488 m, 62 specimens, one of them dead and fragmentary; Station unknown, four specimens and some fragments.

Description. Corallum solitary, unattached, trochoid, more or less curved, rarely straight, fragile. Height from H= 2.5 cm (GCD= 2.3 cm, LCD= 1.9 cm) to H= 3.9 cm (GCD= 2.1 cm, LCD= 1.8 cm), with GCD: LCD= 1.06− 1.21 (in ten specimens chosen randomly, stn. S 7V). Corallum porous distally, comonly with well developed epitheca proximally, resulting in light coralla but with stout appearance. Base narrow, pointed, with corallum tapering quickly from margin to base, sometimes cup-like. Wall costate; C1−2>C3–4, poorly defined, flat, with small digitiform processes and inconspicuous interseptal grooves. Calices irregular, rarely circular. Septa up to 60 with S5 incomplete (12 S5), but more commonly with 48 in four cycles according to the formula S1≥S2>>S3<S4 (GCD= 1.6 cm). S1−S2 dominant, exsert, more than S3, with S4 following S1 and S 2 in the projection; S1−S2 wide, particularly their upper margin with S1 sometimes slightly larger, and their inner edges smooth; S3−S4 narrow. Inner edges of S3 even and of S4 distally even and irregular proximally; S1−S3 straight, subvertical; S4 more or less curved and joining before S3 deep in the fossa, sometimes also joining with S3 (Pourtalès plan), or free; S1, S2 and S4 merge with columella (S4 fused as a single septum), with S3 shorter. Septal faces with small pointed granules. Fosa deep, containing a columella elongated or circular, spongy, nondiscrete, only rarely demarcated from septa by groove and formed by numerous densely packaged rods, sometimes whirled. Corallum of live specimens brown; skeleton white distally and greyish basally.

Remarks. Corrosion by Lumbrineris was observed in specimens from stn. S 7V. The worm was previously known on this species only in three stations, one of them also at Le Danois Bank (Zibrowius et al. 1975; Zibrowius 1980).

The corallum is light and fragile, and most specimens were broken. Many specimens show regeneration, and breakage occurs naturally perhaps favoring asexual reproduction. As a consequence, irregularities in the axial elements are common, and frequently, a whole new corallum develops from a fragment. S5 is never complete, and only a few exosepta S4 are substituted by entosepta, with at most, and normally, five septa between two dominants S1−S2.

Specimens were collected at deeper depths than the range known previously for the species in the Bay of Biscay and nearby areas (137–463 m, see Zibrowius et al. 1975; Zibrowius 1980, 1985), but are in accordance with the range of 80−850 m given by Cairns & Chapman (2001) in the Eastern Atlantic.

A species known from the north-eastern Atlantic and the Mediterranean, although rarely recorded. First record since the original description of Duncan (1873) corresponds to Zibrowius et al. (1975). Collected previously from Le Danois Bank (Zibrowius 1980).