Scalarispongia canus, Kim & Sim, 2020

Kim, Young A & Sim, Kyung Jin Lee and Chung Ja, 2020, Seven new species of two genera Scalarispongia and Smenospongia (Demospongiae: Dictyoceratida: Thorectidae) from Korea, Journal of Species Research 9 (2), pp. 147-161 : 148-151

4. Scalarispongia canus n. sp. ( Figs. 5 , 6 )

ḡNjċflųğãḓậ (ljÿ)

Type specimen. Holotype (NIBRIV0000862771), Korea: Seopjikoji, Goseong-ri, Seongsan-eup , Seogwipo-si , Jeju-do, 17 Mar 2003, collected by K.J. Lee, intertidal zone, rocky substrate, deposited at NIBR.

Description. Thick encrusting sponge, size up to 5.5 × 4.5 × 2.5 cm. Surface covered with grayish-black membrane and dense exposed skeletal fibres in light beige col- or which look like thin hair. Oscules not open on surface. Color in life, dark gray or black. Texture firm and compressible.

Skeleton: Skeletal structure with three dimensional arrangement. Primary fibres cored spicules, 80-140 μm in diameter. Secondary fibres, 40-100 μm in diameter, usually web type. Ladder-like skeletal structure mostly occurred at surface and choanosome. Skeletal fibres arranged regularly but could be in some part irregular. Length of bridged secondary fibres between primary fibres, 350-700 μm and 700-1,000 μm. Skeletal fibres are easily broken. Fibres are very thick outside of sponge.

Etymology. The species name, canus , is named after gray color of emerging skeletal fibres from the sponge surface.

Remarks. This new species is unique because the skeletal structure arranged in three dimensions. Surface covered with dense exposed ladder-like skeletal fibres like beige hair. Ladder-like skeletal fibres occur at the choanosome and sponge base. Diameter of fibres is thicker than other species of Scalarispongia .

Figures

Fig. 5. Scalarispongia canus n. sp. A, external morphology; B, surface under the dissecting microscope; C, D, choanosome skeletal struc- ture; E, F, ladder-like skeletal structure; G, irregular skeletal structure near surface; H, emerging skeletal structure. Scale bars: A=2 cm, B=0.1 cm, C, D=200 μm, E-H =100 μm.

Fig. 6. Scalarispongia canus n. sp. A, skeletal structure; B, irregular skeletal structure; C, D, choanosome irregular skeletal structure. Scale bars:A=200 μm, B-D=100μm.