Desmoxya pelagiae, VAN SOEST & HOOPER, 2005

Morrow, Christine, Cárdenas, Paco, Boury-Esnault, Nicole, Picton, Bernard, Mccormack, Grace, Soest, Rob Van, Collins, Allen, Redmond, Niamh, Maggs, Christine, Sigwart, Julia & Allcock, Louise A., 2019, Integrating morphological and molecular taxonomy with the revised concept of Stelligeridae (Porifera: Demospongiae), Zoological Journal of the Linnean Society 187, pp. 31-81 : 70

DESMOXYA PELAGIAE VAN SOEST & HOOPER, 2005

( FIG. 20A–H)

Desmoxya pelagiae Van Soest & Hooper, 2005 (pp. 1368–1370, fig. 2a–h).

Material examined: Holotype ZMA POR18145 , M2004 BX33A, Rockall Bank, S part, 55°30.288′N, 15°47.148′W, 2 September 2004, 673 m.

BELUM Mc 7764, 54°4.435′N, 12°31.507′W, CE10004 of RV Celtic Explorer, 27 May 2010, coll. C. Morrow, det. C. Morrow.

DNA sequences: From BELUM Mc 7764, we sequenced partial CO1 (GenBank accession no. KC876696 ) and 28S (D3–D5, GenBank accession no. KF018109 ). The 18 S GenBank sequence KC902064 is from the same specimen .

Remarks: A re-examination of the type specimen of Desmoxya pelagiae found acanthostyle spicules and unidirectional spines on the raphides (similar to onychaetes) that were overlooked in the original description ( Fig. 20 shows an SEM of the spicules from the type specimen). The acanthostyles are relatively scarce and confined to the basal region of the sponge. They measure 288– 314– 353 µm × 9–10 µm (N = 6; measurements taken at middle portion of shaft), the heads of the acanthostyles are ~12 µm across.

The presence of acanthostyles and onychaetes suggests an affinity with Tedaniidae ( Poecilosclerida ). Figure 20G, H illustrates the spicule composition in Desmoxya # pelagiae and Tedania (Trachytedania) cf. ferrolensis (Cristobo & Urgorri, 2001) , respectively. Both species share strongyles, raphides and acanthostyles. In addition, Desmoxya pelagiae has bow-shaped acanthose microscleres with unidirectional spines.