Sarcotragus seogwiensis, Sim & Lee & Kim, 2016

Sim, Chung Ja, Lee, Kyung Jin & Kim, Hyung June, 2016, Ten new species of genus Sarcotragus (Demospongiae: Dictyoceratida: Irciniidae) from Korea, Journal of Species Research 5 (3), pp. 443-458 : 444

1. Sarcotragus seogwiensis n. sp. ( Fig. 1 )

Type specimen. Holotype (NIBRIV0000325789), Korea: Seogwi­dong, Seogwipo­si , Jeju­do, 12 Nov 2001, Lee KJ, by SCUBA, depth 15 m, deposited in the NIBR.

Description. Massive, hemispherical sponge, size up to 13 × 9 × 3.5 cm, conulous surface covered with thick filamentous membrane. Conules, low without emergent terminal fibres, but fine fasciculate fibres distributed un­ der surface. Oscules very rare, 3 mm in diameter, colour in life dark gray. Texture firm and compressible. Choanosome lacunose. Subdermal skeletal fibres well devel­ oped ( Fig. 1B ).

Skeleton: Fasciculate primary fibres, cylindrical net, appeared with wads of filaments. Primary fibres fascicles network, 200­300 μm in diameter under membrane, and 600­1000 μm in diameter at choanosome. Branch type of secondary fibres, light fasciculates, 50­200 μm in diameter. Secondary web, variety of wide in diameter. Filaments, 5 μm in diameter, and terminal knobs, 10-12 μm in diameter.

Etymology. This species is named after the type locality Seogwidong, Jeju­do, Korea.

Remark. This new species is similar to Sarcotragus dentilus n. sp. in sponge shape, but differs in surface membrane. Filamentous membrane of this new species is not perforated, and numerous thin branched fibres are distributed under membrane.

Figures

Fig. 1. Sarcotragus seogwiensis n. sp. A, entire animal; B, subdermal skeletal structure; C, fine skeletal structure under membrane; D, pri­ mary fibres fascicles; E, fasciculate branched secondary fibres; F, web of secondary fibres. Scale bars:A=2 cm, B=200 μm, C-F=100 μm.