[2] As in other members of the genus, the upper surface of the disc and the arms is covered with paxillae, pillar-like spines with truncated ends.

[2] The largest specimen from Tagus Cove in the Galapagos Islands had a radius, measured from the centre of the disc to the tip of the arms, of 41.5 centimetres (16.3 in).

[2] The site at Tagus Cove is species rich because of the upwelling of the nutrient-laden, cool water Equatorial Undercurrent nearby, providing an optimum environment for growth which may encourage gigantism.

[2] More recently, the El Nino event of 1982–3 was particularly severe and afterwards, Luidia superba was no longer to be found in its previous location in Tagus Cove.

[2] Unfortunately they were empty except for a few sea urchin spines, but like other members of its genus, Luidia superba is likely to be an opportunistic predator of large benthic fauna and a scavenger.