Antedon serrata A. H. Clark, 1908a

Obuchi, Masami, 2020, Shallow-water Comatulids (Echinodermata: Crinoidea: Comatulida) of the Ashizuri-Uwakai Sea, Shikoku Island, Southern Japan, Species Diversity 25, pp. 309-328 : 322

29. Antedon serrata A. H. Clark, 1908a

[Japanese name: Togebane-umishida]

Morphology. Centrodorsal hemispherical, 1.8–2.0mm across; polar area 0.4–0.6 times of centrodorsal diameter. Cirri delicate, LII, up to 14 segments, 6 mm long, arranged in two to three rows; distal end of segments flared, overlapping base of following; c5–8 longest, L/ W 2.0; no aboral ornamentation excepting opposing spine. Radials invisible. IBr series composed of 2 ossicles with articulation constricted; each ray separated well. Arms 10, up to 40 mm long; brachials slender in distal half arms; first arm syzygy at br 3+4; distal intersyzygial interval 3. Comparative pinnule length P 1>P 2 <P 3 =P 4 <P 5; P 1 enlarged, flexible; proximal to middle pinnules with segments distally flared and rugose, making profiles knotty. Disk hemispherical, three times as wide as centrodorsal, with fleshy papillae, especially on anal cone.

Posture. Attached on underside of boulders with arms spread.

Coloration in life. Widely various: BIK-EC-CR0076 with rays banded red-brown and white, and disk white with small brown spots, BIK-EC-CR0077 with rays light brown but pink at proximal part, and yellow disk, and BIK-EC-CR0078 uniformly light brown with small white spots.

Distribution. Aomori, northern Japan ( Kogo 1998) to Hainan Island (Liao and A. M. Clark 1995).

Remarks. Genus Antedon de Fréminville, 1811 is characterized by P 3 similar to following pinnules, and P 2 intermediate between P 1 and P 3 in lengths. This species is unique in having segments of the proximal pinnules remarkably flared and spinose on the distal end.