Sarcotragus mamillus, 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 : 452-454

10. Sarcotragus mamillus n. sp. ( Fig. 12 )

Type specimen. Holotype (NIBRIV0000554219), Korea: Mureungachi, Daejeong­eup, Seogwipo­si , Jeju­do, 15

Aug 2015, Moon SE, by SCUBA, Depth 20 m, deposited in the NIBR.

Description. Irregular mass, size up to 12 × 8 × 4 cm. Surface, slightly protruding like mamillate form, low conules with filamentous membrane. Oscules, 4­6 mm in diameter, open at protruding surface. Colour in life gray. Texture very soft and compressible. Choanosome lacunose, subdermal skeletal fibres well develope.

Skeleton: Subdermal skeletal structure very thick, primary fibres, 400­800 μm in diameter, wide secondary web, 600­1400 μm in diameter, bridged secondary fibres, 100­400 μm in diameter. Skeletal structure of basal part, very thick, it’s big different from one near surface. All primary and secondary fibres have numerous irregular perforations. Filaments, 3­5 μm in diameter, terminal knobs, 10 μm in diameter.

Etymology. This species is named after surface mamillate form.

Remark. This new species is similar to Sarcotragus geomunensis n. sp. in collagenous secondary web, but differs in choanosomal primary fibres. Surface membrane of this new species has no perforation.

Figures

Fig. 12. Sarcotragus mamillus n. sp.A, entire animal; B, subdermal skeletal structure; C, secondary web; D, branched secondary fibres; E, F, skeletal structure at the base of sponge. Scale bars:A =2 cm, B=200 μm, C-F=100 μm.