Mariametridae A. H. Clark, 1909b

Obuchi, Masami, 2020, Shallow-water Comatulids (Echinodermata: Crinoidea: Comatulida) of the Ashizuri-Uwakai Sea, Shikoku Island, Southern Japan, Species Diversity 25, pp. 309-328 : 320

Family Mariametridae A. H. Clark, 1909b 21. Lamprometra palmata ( Müller, 1841) [Japanese name: Higasa-umishida]

Morphology. Centrodorsal low hemispherical, 5.7– 8.4 mm across; polar area flat, 0.4–0.6 times of centrodorsal diameter. Cirri L– LXXI, up to 35 segments, 28 mm long, arranged in three rows; c8–15 longest, L/ W 1.2; distal half segments with low aboral process . Radials invisible. All division series, I–IVBr, composed of 2 ossicles with straight lateral expansion; Arms up to 48, 135 mm long; first arm syzygy at br 3+4; distal intersyzygial intervals 3–16. Comparative pinnule length P 1 <P 2>P 3>P 4 =P 5; P 1–3 enlarged; segments smooth, L/W up to 1.4. Disk flat stellate, two to three times as wide as centrodorsal.

Posture. Nocturnal. Fully exposed on rocky pinnacles in nighttime, forming arcuate fan.

Coloration in life. Rays banded with brown, red and cream, with white and purple blotches.

Distribution. Sado Island, northern Japan ( Honma and Kitami 1978) to Great Barrier Reef ( Rowe and Gates 1995). Tonga to Mauritius and Red Sea (A. H. Clark 1941). Guam ( Kirkendale and Messing 2003).

Remarks. Genus Lamprometra A. H. Clark, 1913 is characterized by enlarged but not spine-like proximal pinnules, of which P 2 is the largest. Recent taxonomic revision showed the monospecificity of this genus ( Rankin and Messing 2008).