Solaster 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 : 498-500

Solaster sp.

FIGURE 17A

Description

Arms seven, elongate and tapering, disc thick ( Fig. 17A ). Abactinal paxillae widely spaced in transverse rows proximally along arm. Distinct carinal groove present along each arm ( Fig. 17A ). Marginal series paxillate, approximately 50 to 60 per arm, but full count unclear from image. Furrow spines approximately 2, per plate, subambulacral spines 3 to 4.

Color was pink with dark highlights.

Comments

Identification of this individual to species was not possible owing to its unusual angle. Solaster notophrynus Downey 1971 has seven arms, but displays wider arms with more densely distributed paxillae. Solaster endeca displays a similar linear pattern along each arm radius, and has a consistent number of furrow and subambulacral spines. However, arm number on this individual is inconsistent (n=7) versus 10 in S. endec a and paxillar patterns differ from shallow-water forms. Solaster endeca is only known off the east North American coast to 549 m and displays a southern limit in the western Atlantic near Cape Cod, casting doubt on the possibility of being this species. This and the other solasterid observed ( Fig. 17B ) showed differing arm number, seven here and eight in Fig. 17B , but differs in having much more pronounced abactinal paxillae with fewer marginal paxillae and a reticulate pattern present across its abactinal surface similar to Crossaster or Laetmaster .

Ecological Comments

The individual was observed upside down within the canopy of dead coral, presumably feeding on prey. While there was abundant detritus, other solasterid species are predatory and it is likely that this one was as well, with a prey item out of sight.

Image Observed

Retriever Seamount, North Atlantic, 39.838493, -66.229423, 1933 m.

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Figures

FIGURE 17. Solaster and solasterid-pterasterid predation event.A. Solaster sp. feeding. B. Solasterid-pterasterid predation. Blake Spur Trough, North Atlantic, 3611 m.