A New Species of Clypeaster (Echinodermata, Echinoidea) from San Felix Island, with a Key to the Recent Species of the Eastern Pacific Ocean

Abstract

Clypeaster isolatus sp. nov. is described from 61 specimens taken off San Felix Island. It is distinguished by its concave oral side, moderately high test (23 to 36 percent of the test length), broad paired petals, primary spines without a hyaline point, short, stout aboral primary spines and three to six primary tubercles on the ridge between the pore pairs. Data on test morphology are given for use in analysis of intraspecific variation. The new species is most closely related to C. australasiae from southeastern Australia. This affinity to the Australian fauna supports the theory of west-wind-drift dispersal.