Isodictya lankesteri ( 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

Isodictya lankesteri ( Kirkpatrick, 1907)

( Figure 5m –p )

Restricted synonymy: Cercidochela lankesteri Kirkpatrick, 1907 .

Material examined: 2 specimens collected at station 16 ( SOI; 60°40,992'S, 46°14,560'W; 104 m; 7/3/2012; MACN-In 44378; IEO-CSIC Col.) .

Description: One large arborescent specimen, 43 cm high, and a small broken cylindrical specimen, light beige in colour. The larger and complete specimen has a velvety surface, with multiple oscula evident on the branches, the oscula are roughly aligned. The rhizoid anchor structure is conspicuous and has sediment grains and small pebbles attached ( Fig. 5m ). The skeleton is composed of ascending plumose multispicular tracts of oxeas. These are connected by other oxeas ( Figure 5p ). Microscleres are abundant and dispersed throughout the choanosome. Megascleres are oxeas 270–430 µm by 10–20 µm; microscleres are canonochelae of 50–70 µm ( Figure 5n, o ).

Remarks: This species was previously recorded by Hentschel (1914), Burton (1929), Desqueyroux (1975), Campos et al. (2007) and Fernández et al. (2021), amongst others. 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.