(Tables 1−3)
Desmophyllum cristagalli: Zibrowius 1980: 117, pl. 61, figs. A– O, pl. 62, figs. A–M.—Monteiro Marques & Andrade 1981: 88.—Zibrowius 1985: 317, tab. 2.—Altuna & García Carrascosa 1990: 56.—Ramil Blanco & Fernández Pulpeiro 1990: 27.—Álvarez Claudio 1993: 417.—Altuna Prados 1994 a: 467, pl. 12, fig. B, pl. 14, fig. B.—Altuna Prados 1994 b: 55.— Altuna Prados 1994 c: 78 (fig. 1).—Álvarez Claudio 1994 c: 465.—Altuna 1995: 90.—Brito & Ocaña 2004: 379, fig. 156.— Reveillaud et al. 2008: 322 (tab. 1), 325 (fig. 4).—Altuna 2010: 21.
Desmophyllum dianthus: Cairns & Chapman 2001: 35 (tab. 1). —MMA 2007: 15. —OSPAR 2008: 38.
Material examined. Le Danois Bank, 2003: Stn. V 5, 544 m, three specimens. Le Danois Bank, 2008: Station unknown, seven specimens alive, 16 specimens dead, and fragments; Stn. R 1 R 8, 677 m, 11 very small specimens, only one alive, and fragments. Avilés Canyon system: Stn. R 1, 500 m, eight specimens, six of them dead. Galicia Bank: Stn. G 5, 859 m, one specimen on a net fragment; four specimens, one of them dead on Madrepora oculata; two specimens, one of them dead on Lophelia pertusa; three specimens two of them dead; four specimens, one of them dead on unidentifiable coral debris; Stn. G 6, 761 m, 13 specimens, one on M. oculata, six of them dead; Stn. V 5, 877 m, three specimens, one of them on M. oculata, and a dead fragment; Stn. V 6, 766 m, five specimens, two of them dead; Stn. V 8, 780 m, numerous specimens; Stn. R 2, 614 m, three specimens, two of them dead on M. oculata.
Remarks. Specimens are highly variable, and sometimes large-sized. Those from stn. R 1 R 8 are very small juveniles and are identified as Desmophyllum cristagalli with caution. One of them is vermiform (H= 2.0 cm; GCD= 0.4 cm), and the others turbinate and of similar size (H= 0.3−0.6 cm; GCD= 0.1−0.2 cm). They show a certain variability in the structure of the columella, ornamentation of the wall and septa (smooth of finely granulated), calicular margin and number of septa. Generally speaking, the fossa is deep and there are 24 septa hexamerally arranged in three cycles (S 1>S 2>S 3), although in some specimens there is an incipient cycle S 4 joining S 1 in the exsert projection, with an irregular lanceted calicular margin. S 1 and S 2 descend vertically into the fossa, with their inner edges straight or slightly sinuous. The columella is formed by a unique small plate or 2− 3 rods.
Desmophyllum cristagalli was recorded in all the surveys and sampling areas. Particularly remarkable is stn. G 5, with specimens living on Lophelia pertusa and Madrepora oculata. This is frequent in the species, commonly associated to the white coral banks (Zibrowius 1980; Cairns 1994). Desmophyllum cristagalli is an abundant coral in the north-Iberian bathyal and the Bay of Biscay, with its type locality in the southern sector (Capbreton, see Zibrowius 1980).
The author cannot agree in considering Desmophyllum cristagalli from the north-eastern Atlantic and the Mediterranean a synonym of Desmophyllum dianthus (Esper, 1794) (see Cairns 1994; Cairns & Chapmann 2001). The binomen D. dianthus is now used for Atlantic Iberian material (Wienberg et al. 2009), Mediterranean (Taviani et al. 2011), or for specimens from other Atlantic areas (Kitahara 2007). D. cristagalli has been used widely up til now, the holotype was collected from the Bay of Biscay (Capbreton Canyon), and it is in Paris (see Zibrowius 1980). D. dianthus, was described and illustrated poorly and has a confuse history (Zibrowius, com. pers.). According to Cairns (1994: 27), “we may never know the identity of Esper's D. dianthus from the ‘East Indies’ because the type is lost and the description is brief”. The neotype from Sagami designated by this author (Cairns 1994) was collected from an unknown depth (the holotype from D. cristagalli is also from an unknown depth).
A species widely distributed in the Mediterranean and north-eastern Atlantic in a broad bathymetric range (Zibrowius 1980), with a cosmopolitan distribution (Cairns 1991; Cairns & Parker 1992). This is one of the scleractinian corals most widely distributed worldwide, and with a larger bathymetric range (35−2460 m, see Cairns 1991).