Comaster nobilis ( Carpenter, 1888 )

Obuchi, Masami, 2020, Shallow-water Comatulids (Echinodermata: Crinoidea: Comatulida) of the Ashizuri-Uwakai Sea, Shikoku Island, Southern Japan, Species Diversity 25, pp. 309-328 : 312

3. Comaster nobilis ( Carpenter, 1888) [Japanese name: Hana-umishida]

Morphology. Centrodorsal thin, slightly raised from level of radials, 4.4–5.2 mm across. No functional cirri, except few rudimentary ones and scars. Radials exposed, length 0.3 times of centrodorsal diameter. IBr series composed of 2 ossicles, IIBr of 4(3+4), IIIBr of 2 on outer and of 4(3+4) on inner side of rays, and IV–VIBr of 4(3+4); proximal rays fused by additional interradial plates present, making calyx aborally solid. Arms up to 104, 135 mm long; brachials shorter than broad, with distal ends everted; first arm syzygy at br 3+4; distal intersyzygial intervals 4. Comparative pinnule length PD>>P 1>P 2 =P 3 =P 4 =P 5; PD enlarged. Terminal combs present as far as P 3–5, consisting of 7–17 segments; combs of PD with single, knob-like small teeth; ones of following pinnules with teeth paired, both straight, confluent with lateral margins of pinnule segments; paired teeth on proximal few segments fused into transverse bar. Disk remarkably large, five to eight times as wide as centrodorsal, smooth.

Posture. Fully exposed on rocky pinnacles, with arms in multilayered arrays.

Coloration in life. Various with the most common pattern being arms of yellow to orange and pinnules blotched with white, black, yellow and orange. Some animals almost entirely white with some pinnules blotched with black.

Distribution. Kii Peninsula, Japan ( Kogo 1998) to northern New South Wales, Australia ( Rowe et al. 1986). New Caledonia ( Rowe et al. 1986) to Sri Lanka (A. H. Clark 1931).

Remarks. Genus Comaster L. Agassiz, 1836 is characterized by having numerous arms with the first syzygy at br 3+4, asymmetric bifurcation beyond IIIBr series, and the central mass integrated by interradial plates. This species is unique in almost lacking functional cirri.