Ircinia incrustans, Sim & Lee & Kim, 2016

Sim, Chung Ja, Lee, Kyung Jin & Kim, Hyung June, 2016, Nine new species of genus Ircinia (Demospongiae: Dictyoceratida: Irciniidae) from Korea, Journal of Species Research 5 (3), pp. 483-497 : 484

1. Ircinia incrustans n. sp. ( Fig. 1 )

Type specimen. Holotype (NIBRIV0000554220), Korea: Munseom, Seogwipo­si , Jeju­do, 15 Aug 2015, Kim BI, by SCUBA, Depth 25 m, deposited in the NIBR.

Description. Thin encrusting, size up to 14 × 5 cm wide 0.5 cm thick, attached on shell of oyster. Surface smooth, and covered with thick collagenous filamentous membrane. Conules, rare and low, but easily discerned at side of sponge. Several oscules, 2­8 mm in diameter, opened through sponge. Colour pale grey in life turns to dirty gray in alcohol. Texture firm.

Skeleton: Primary fibres, 150­450 μm in diameter, some thin primary fibres at membrane cored with sands and broken spicules. Choanosome primary fibres not cored mostly and uncored primary fibres not easy to distinguish from secondary fibres. Branched secondary fibres, 250­500 μm in diameter. Filaments, 6-7 μm in diameter, terminal knobs, 13­15 μm in diameter.

Etymology. This species is named after the encrusting habit.

Remark. This new species is characterized by its encrusting form. Thick collagenous filamentous membrane of surface is easily covered out.

Figures

Fig. 1. Ircinia incrustans n. sp. A, entire animal; B, surface skeletal structure; C, closed surface skeletal structure; D, cored primary and secondary fibres; E, F, uncored primary and secondary fibres. Scale bars:A=2 cm, B=200 μm, C-F=100 μm.