Euryspongia radicula, Kim & Sim, 2020

Kim, Young A & Sim, Kyung Jin Lee and Chung Ja, 2020, Eight new species of two genera Dysidea and Euryspongia (Demospongiae: Dictyoceratida: Dysideidae) from Korea, Journal of Species Research 9 (1), pp. 56-67 : 58-63

Genus Euryspongia Row, 1911

5. Euryspongia radicula n. sp. ( Fig. 6 ) ḁNṈOiỢ (ljḏ)

Type specimen. Holotype (NIBRIV0000854520), Korea: Dueokyeo, Gageo-ri, Heuksan-myeon , Shinan-gun , Jeollanam-do, 20 Jul 2007, Kim, H.S., by SCUBA, depth 20 m, deposited in the NIBR.

Description. Thin, small mass, leaf like sponge, size up to 5.5 × 2.5 × 1 cm. Surface smooth with thick primary fibres, not distinct conules, but have sharp conules at side and no oscules. Color in life pale-brown, brown clay in alcohol. Texture soft and compressible.

Skeleton: Skeletal structures very simple. Primary fibres, 80-200 μm in diameter, root-like form at base ( Fig. 6C ). Secondary fibres, rarely branched ( Fig. 6B ), 60-100 μm in diameter. Fibres easily broken.

Etymology. This species name, radicula is named after the root-like shape of primary fibres at base.

Remarks. This new species is very different from other species in Euryspongia by regularly arranged primary and secondary fibres. Primary fibres are very simple, root-like shape at the base. Secondary fibres are very rare. All fibres are easily broken.

6. Euryspongia spina n. sp. ( Fig. 7 ) ḦṄṈOiỢ (ljḏ)

Type specimen. Holotype (NIBRIV0000854521), Korea: Dueokyeo, Gageo-ri, Heuksan-myeon , Shinan-gun , Jeollanam-do, 20 Jul 2007, Kim, H.S., by SCUBA, depth 20 m, deposited in the NIBR.

Description. Mass sponge, size up to 7 × 5.5× 3 cm. Surface, smooth with protruding primary fibres, and indistinct conules, but have sharp conules at side. Oscules not open. Color in life beige-brown, brown clay in alcohol. Texture soft and compressible.

Skeleton: Skeletal fibres fence-like and especially secondary fibres complex web type at base. Primary fibres, 200-350 μm in diameter, with numerous spines at the end of fibre. Secondary fibres, 30-130 μm in diameter, rarely occur on surface.

Etymology. This species name, spina , is named after its primary fibres with spines near the surface.

Remarks. Skeletal structure is fence-like. Bridged type secondary fibres are between primary fibres near the surface, 1800-2000 μm long and 80-130 μm in diameter. Web type secondary fibres are usually arranged at the base of fibres.

7. Euryspongia flabellum n. sp. ( Fig. 8 ) AENjṈOiỢ (ljḏ)

Type specimen. Holotype (NIBRIV0000854522), Korea: Dueokyeo, Gageo-ri, Heuksan-myeon , Shinan-gun , Jeollanam-do, 20 Jul 2007, Kim, H.S., by SCUBA, depth 20 m, deposited in the NIBR.

Description. Wide thin folded leaf-like shape sponge, size up to 16 × 10 × 0.3-0.4 mm. Surface smooth with thick primary fibres, not distinct conules. Oscules rare 1-2 mm in diameter. Color in life beige-brown, brown clay in alcohol. Texture soft and compressible.

Skeleton: Numerous primary fibres, arranged side by side, 150-250 μm in diameter. Secondary fibres, 30-100 μm in diameter with diverse-sized openings near primary fibres ( Fig. 8D, 8E ).

Etymology. This species name, flabellum , is named after its fan shape form.

Remarks. Primary fibres are like a bundle ( Fig. 8C ), and thin secondary fibres are between primary fibres. The wide thin leaf-like shape in this sponge is very unique.

8. Euryspongia linea n. sp. ( Fig. 9 ) ŪDṈOiỢ (ljḏ)

Type specimen. Holotype (NIBRIV0000854523), Korea: Neunggeol, Ulleung-gun , Gyeongsangbuk-do, 2 Oct 2001, Kim, H.S., by SCUBA, depth 20 m, deposited in the NIBR.

Description. Thick encrusting sponge, size up to 7 × 3 × 2 cm. Surface smooth with long rope-like primary fibres occur, no oscules. Color in life beige, brown clay in alcohol. Texture soft and compressible.

Skeleton: Primary fibres, 150-300 μm in diameter. Long rope-like primary fibres emerging from surface. Secondary fibres, very rare, 40-100 μm in diameter.

Etymology. This species name, linea , is named after its long string-like primary fibres.

Remarks. String-like primary fibres are very unique and cored with large sized sands.

Figures

Fig. 6. Euryspongia radicula n. sp. A, external morphology; B, skeletal structure near base; C, D, cored primary fibres; E, branched second- ary fibres; F, bridged secondary fibres. Scale bars:A =2 cm, B=200 μm, C-F=100 μm.

Fig. 7. Euryspongia spina n. sp. A, external morphology; B, skeletal structure under a dissecting microscope; C, skeletal structure at base; D, skeletal structure at mid-section; E, F, primary fibres near surface; G, primary fibres near conules; H, primary and secondary fibres. Scale bars:A=2 cm, B=1 cm, C, D=200 μm, E-H=100μm.

Fig. 8. Euryspongia flabellum n. sp. A, external morphology; B, surface close up; C-E, skeletal structure; F, primary fibres with spine; G, secondary fibres; H, skeletal structure under a dissecting microscope. Scale bars: A=2 cm, B=1 cm, C-E=200 μm, F, G=100 μm, H =1 cm.

Fig. 9. Euryspongia linea n. sp. A, external morphology; B, skeletal structure under a dissecting microscope; C, D, skeletal structure; E, F, cored primary fibres; G, skeletal structure with membrane; H, primary fibres near conules. Scale bars: A =2 cm, B=1 cm, C=200 μm, D-H =100 μm.