Atheraster sp.

Mah, Christopher L., 2024, Two New Taxa of Goniasteridae (Asteroidea, Echinodermata) and Noteworthy Observations of Deep-Sea Asteroidea by the NOAA Ship Okeanos Explorer in the North and Tropical Atlantic, Zootaxa 5432 (4), pp. 461-508 : 473-474

Atheraster sp.

FIGURE 5

Description

Body stellate (R/r=2.7), arms elongate, tapering, triangular in shape. Disc thick, interradial arcs straight to weakly curved. Abactinal plates closely arranged, disc plates similar in size, strongly convex, sharply set off from arm plates which are approximately 2 to 3X the size. Disc plates and arm plates with sharp pointed spinelets with broad round bases, arm spinelets larger than those on disc. Marginal plates, approximately 40–60 per interradius (arm tip to arm tip), wide, lateral facing on disc but with greater dorsal facing distally on arms. A single prominent, conical spine present on each superomarginal and inferomarginal plate, all forming linear series.Actinal surface out of view. Color in life is white to tan on disc with arms colored light orange with darker highlights on proximal abactinal plates and superomarginal plates.

Comments

Atheraster was described to accommodate Circeaster arandae Mah, 2006 , which bears well-developed spines present on the marginal plates as well as arm plates which are demonstrably larger than those on the disk. Although the image does not show full details, such as the actinal surface, observable characters clearly place this species into Atheraster , which has not been previously reported from the Atlantic. Based on the variably sized abactinal spinelets, this appears to be an undescribed species.

Ecological Comments

This species was observed feeding on bamboo coral (family Isididiae ) which is a taxon fed upon by multiple hippasterine asteroids, such as Evoplosoma (e.g., Mah 2020).

Occurrence

Hopscotch Seamount, 2501 m.

Image Studied

Hopscotch Seamount, North Atlantic, 33.675913 -52.993592, 2501 m.

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Figures

FIGURE 5. Atheraster sp. undescribed. Hopscotch seamount, North Atlantic, 2501 m.