Polymastia sasuensis, Kim & Sim, 2021

Kim, Young A & Sim, Chung Ja, 2021, Ten new species of families Suberitidae and Polymastiidae (Demospongia: Heteroscleromorpha) from Korea, Journal of Species Research 10 (2), pp. 168-183 : 178

8. Polymastia sasuensis n. sp. ( Fig. 10 )

ṷ÷ųāḁḍ(ṳḋ)

Type specimen. Holotype (NIBRIV0000881729), Korea: Sasudo, Chuja-myeon, Jeju-si , Jeju-do, 2 Jun 2013, by SCUBA, depth 30-35 m, deposited in NIBR.

Description. Cushion shape sponge, size up to 7 × 6.5 × 4 cm. Surface with numerous protruding small papillae. Oscules open at apical of each conical papillae, 0.5 mm in diameter. Color is grayish green. Texture firm.

Skeleton: Ectosome 1 mm thick and densely packed with spicules and collagen. Thin long tylostyles brushed out to the surface in combination with medium and small sized spicules. In choanosome, long spicules around 900 μm, mix with medium and small sized spicules. Large tylostyles, 700-1,100 × 8-15 μm, medium tylostyles, 500-600 × 10 μm and small tylostyles, 150- 350 × 3-7 μm.

Etymology. The species name, sasuensis, is named after type locality Sasudo, Chuja-myeon, Jeju-do.

Remarks. This new species is similar to P. viridis in sponge shape but differs in thickness of spicules. In P. viridis , large and small tylostyles are thicker than P. sasuensis .

Figures

Fig. 10. Polymastia sasuensis n. sp. A, external morphology; B, underside of sponge; C, spicules with ectoderm; D, hair-like surface spicules under the dissecting microscope; E, F, tylostyles; G, bundle of tylostyles; H, tylostyles with spongin. Scale bars:A=2 cm, B=1 cm, C, F-H=50μm, E=100 μm.