Isodictya verrucosa ( Topsent, 1913 )

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 : 412-413

Isodictya verrucosa ( Topsent, 1913)

( Fig 5j–l )

Restricted synonymy: Homoeodictya verrucosa Topsent, 1913 .

Material examined: 3 broken specimens collected at stations 2 ( SOI; 60°53'S, 44°33'W; 218 m; 20/2/2014; IEO-CSIC Col.) and 10 ( SOI; 60°59'S, 46°43'W; 307 m; 5/3/2014; MACN-In 44381) .

Description: Erect and digitiform, with a hispid surface ( Figure 5j ). Megascleres are thick straight or slightly curved oxeas 540–780µm/ 10–30µm. Small isochelae of 25–35 µm ( Figure 5k–l ).

Remarks: The type locality of this species is the Burdwood bank, located in a subantarctic region. Other subantarctic records include the northernmost record at the Argentinean shelf-break region (sample labelled as CC-02-03 L64/14, corresponding to 43°26.11’S and 59°47.62’W) ( Schejter et al. 2006). It has been also recorded in Antarctic waters by Boury-Esnault & Van Beveren (1982), Burton (1929), Mothes & Lerner (1995), Ríos (2006) and Fernández et al. (2021). Antarctic specimens have larger oxeas, as also reported by Ríos (2006). This is a new record for the SOI.

Figures

FIGURE 5. a–f. Crella (Pytheas) crassa. a, general morphology, scale: 1 cm; b, Strongyle, scale: 110 µm; c, Acanthostyle, scale: 60 µm; d, Isochela, Scale:12.5 µm; e–f, Skeleton, scale: 200 µm; g–i. Isodictya kerguelenensis. g, General morphology, scale: 4 cm; h, isochelae, scale: 8 µm; i, Oxea, scale: 170 µm; j–l. Isodictya verrucosa. j, General morphology, scale: 3 cm; k, Isochela, scale: 12 µm; l, Oxea, scale: 200 µm; m–p. Isodictya lankesteri. m, General morphology, scale: 8.5 cm; n, Canonochela, scale: 30 µm; o, Oxea, scale: 130 µm; p, skeleton, scale: 100 µm.