Alloceramaster irritatus is a species of sea star in the family Goniasteridae found southeast of Norfolk Island and off New Caledonia.
Description The species has a pentagonal body. Abactinal plates are covered by a granular layer that forms a discrete cover over individual plates. Radial plates are wide, round to polygonal, and display peripheral rectangular granules. There are 6 superomarginal plates and 8 to 9 inferomarginal plates (with the distalmost small, upturned, and adjacent to the terminal plate). Superomarginals are covered by widely spaced granules (20–40) on a raised surface, otherwise covered by closely spaced round granules. Inferomarginal plates are numerous and dense, covered by polygonal to round granules. Furrow spines number 7 to 9 (distally 5 or 6). Subambulacral spines are arranged in 3 to 4 irregular series, decreasing in size from those adjacent to the furrow to those adjacent to the actinal plates.
Distribution and habitat This species is known from southeast of Norfolk Island (Norfolk Basin) at 530 meters and from off New Caledonia at depths of 428 to 470 meters.
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