Haliclona (Gellius) cf. arcuarius ( 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 : 423

Haliclona (Gellius) cf. arcuarius ( Topsent, 1913)

( Fig 12a–c )

Restricted synonymy: Gellius arcuarius Topsent, 1913 , Calyx arcuarius ( Topsent, 1913) , Vagocia arcuaria ( Topsent, 1913) .

Material examined: 2 specimens collected at station 11 ( SOI; 60°53'S, 42°35'W; 487 m; 10/3/2014; MACN-In 44361; IEO-CSIC Col.) .

Description: Fragments of two specimens, probably laminar or cup-like in form, beige in colour ( Figure 12a ). The skeleton is an isotropic reticulation, with several aquiferous canals present ( Figure 12b ). Spicules are oxeas of 320–380 µm by 20 µm ( Figure 12c ). No microscleres.

Remarks: The variability reported for this species was previously discussed by Göcke & Janussen (2013), among other authors and our specimens fit well with the description provided by these authors. Goodwin et al. (2012) suggested that this species conformed the current definition of Haliclona (Gellius) group, based on skeletal characteristics, as it was previously classified within the genus Calyx . Unlike Koltun’s (1964) and Topsent’s (1913) descriptions of their specimens, our samples lack microscleres. This species has been reported for Antarctic waters by Topsent (1913), Koltun (1964), Desqueyroux (1975) and Göcke & Janussen (2013), and its type locality is located at the SOI.

Figures

FIGURE 12. Haliclona (Gellius) cf. arcuarius, a. general morphology, scale: 1.6 cm; b. oxea, scale: 1,6 cm choanosomal skeleton, scale: 200 µm;