Scientific name: Gorgonocephalus arcticus

Phylum: Echinodermata

Class: Ophiuroidea

Description: Basket star is yellowish to brown in color, and with a disk to 38mm across. The disk is naked with spines on 5 pairs of radial ridges and scattered in between. The arms branch repeatedly, and outer parts form a dense tangle.

Distribution: Basket stars are found from Arctic to Cape Cod , from sub-tidal to more than 1200m on a variety of bottoms.

Locomotion: Basket stars use their flexible articulated arem primarily for crawling or clinging. Skeletal arrangement of arms allows for extensive “lateral” movement but have no flexibility parallel to the oral-aboral axis. Though tube feet lack suckers and ampullae, they have well-developed muscles in their wall.

Food gathering: Basket stars utilize suspension feeding to capture relatively large swimming prey (crustaceans and polychaetes). This is accomplished using podia and arm spines. At night, at duck basked stars emerge from hiding places and assume feeding positions, with their positions, with their branched arms held fan-like into position with ebb and flow of the tides.

Gas exchange: Basket star possesses 10 invaginations of the body wall called bursae, which open to the outside through ciliated slits. Gases are exchanged between the flowing water and the body fluids.

Reproduction: The sexes are separated. They also have a free-swimming larval stage. Ophiuroids possess from 1 to many gonads attached to the peritoneal side of each bursa. Gametes are released into the bursae and expelled through the slit.

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OSC Research

Mercier Lab - Research on reproduction, larval development, ecology and growth is carried out on a wide variety of marine invertebrates in this lab.