New Hyocrinid Crinoids (Echinodermata) from Submersible Investigations in the Pacific Ocean

Abstract

A few specimens belonging to the deep-sea family Hyocrinidae (stalked Crinoidea, Echinodermata) collected by submersible in the eastern and western Pacific Ocean are described. Laubierierinus pentagonalis, n. genus, n. sp., from the North Fiji Rise is the first discovery of a hyocrinid crinoid with a pentaradially symmetrical stalk. Hyocrinus biscoitoi, n. sp., from the East Pacific Rise attains large size and has close affinities with H. giganteus from Horizon Seamount. Additional information is given concerning H. foelli found near cold seeps on the Mexican continental margin; H. cyanae, previously collected on New Caledonian slopes; and Calamoerinus diomedae from the Cocos Ridge and Galapagos slopes. For the latter, the first young specimens known document ontogenetic trends in this famous species.