Mycale (Oxymycale) acerata Kirkpatrick, 1907

Schejter, Laura, Cristobo, Javier & Ríos, Pilar, 2024, New records of demosponges (Porifera) from the South Orkney Islands (Antarctica) with a checklist for the region, Zootaxa 5403 (4), pp. 401-430 : 413

Mycale (Oxymycale) acerata Kirkpatrick, 1907

( Fig 6a )

Restricted synonymy: Mycale acerata Kirkpatrick, 1907 .

Material examined: 3 specimens collected at stations 1 ( SOI; 60°28'S, 46°29'W; 139 m; 19/2/2014; MACN-In 44389; IEO-CSIC Col.), 4 ( SOI; 60°55'S, 44°04'W; 256 m; 2/3/2014; MACN-In 44390; IEO-CSIC Col.), and 9 ( SOI; 60°57'S, 46° 01'W; 229 m; 5/3/2014; MACN-In 44391; IEO-CSIC Col.) .

Description: Massive, flexible and soft sponges, beige/light brown in colour. Verrucose surface, with a characteristic reticulate ectosome and a fibrose-reticular choanosome of thick fibers, especially in older parts of the sponge body ( Figure 6a ). One of the specimens is broken and badly preserved. Megascleres are oxeas 750–950/ 20–30 µm. Microscleres are two categories of anisochelae of 70–90 µm (this category is absent in the broken specimen) and 25–55 µm, and raphides in trichodragmata 100–210 µm.

Remarks: This is a common species, very well described and frequently collected in Antarctic and subantarctic waters (e.g. Göcke & Janussen (2013), Ríos (2006), Desqueyroux (1989), Fernández et al. (2021)). It was previously recorded at the SOI by Topsent (1913), Burton (1932) and Koltun (1964).

Figures

FIGURE 6. a. Mycale (Oxymycale) acerata, general morphology, scale: 6 cm; b–f. Mycale (Mycale) bouryesnaultae; b. general morphology, scale: 3 cm, c. mycalostyle, scale: 110 µm; d. anisochelae I, scale 30 µm; e. anisochelae II, scale: 15 µm; f. sigmas, scale: 30 µm.