Biemna erecta Bertolino, Costa & Pansini sp. nov.

urn:lsid:zoobank.org:act: F0A045BB-EE04-4239-94C8-C3025A29B450

Figs 9–10; Table 6

Etymology

The new species is named after its growth form.

Type material

Holotype

CHILE – Puerto Cisnes • Seno Magdalena D; 44.614863° S, 72.958312° W; depth 20 m; 5–10 Aug. 2016; Marco Bertolino leg.; on a vertical wall by scuba diving; CILE 74; MSGN 61496.

Description

HABITUS. Fan-shaped lamellar sponge, about 3 mm thick and 3.5 cm long, with basal peduncle. Surface very hispid caused by megascleres protruding from surface. Colour in life pale yellow, tending to orange (Fig. 9 A–B). Consistency soft, compressible and friable in dry state.

SKELETON. Plumose skeleton formed by dense fibres of spicules whose extremities protrude through surface of sponge, resulting in hispid appearance (Fig. 9C). Choanosome differentiated into two regions composed of axial compressed and extra-axial plumose fibres (Fig. 9 D–E). Basal peduncle formed by ascending central fibres with radial spicules (Fig. 9F).

SPICULES. Megascleres: Styles smooth and sinuous, with regular round heads (Fig. 10A), 1810.5– (2033.3)–2295 μm long and 15–(17.5)–20 μm thick; tylostyles/subtylostyles slightly curved near the head (Fig. 10B), 350–(607.5)–960 μm long and 10–(18.75)–30 μm thick. Microscleres: Two categories of raphids; I, sinuous and thin raphids (Fig. 10C), 87.5–(115)–167.5 μm long; II, short and thick raphids, with small scattered spines, similar to raphidioid microxeas, 23.4–(36.55)–42.5 μm long and 2 μm thick (Fig. 10D). C-shaped sigmas with microspined extremities clearly divided into two size categories: sigmas I, (Fig. 10E), 140–(159.5)–180 μm long and 5–(5.7)–7.5 μm thick; and sigmas II, (Fig. 10F), only 10–(14.5)–17.5 μm long.

Habitat

Species lives on a vertical wall at a depth of 20 m.

Remarks

We have recorded three new species of the genus Biemna and have therefore decided to make combined remarks after their description.