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Overview

Ophiarachnella gorgonia, commonly known as the smooth brittle star, is a widespread echinoderm found throughout the Indo-West Pacific region. It is frequently encountered in shallow marine environments, typically hiding under rocks or within coral rubble on reefs.

Distribution & habitat

This species is widely distributed across the Indo-West Pacific, ranging from East Africa to the West Pacific, though it is notably absent from southeastern Polynesia. It inhabits various reef environments, including lagoon, pinnacle, and seaward reefs, often sheltering in crevices or beneath rubble from the intertidal zone down to depths of approximately 278 meters.

Appearance

The smooth brittle star is characterized by a central disc that is densely covered in fine granules, with the exception of its distinct, naked, and elongate radial shields. Its arms are generally smooth and lack the prominent granulation seen on the disc, often featuring short, comb-like spines. While the most well-known color pattern consists of green and white markings on the disc and banded arms, other color morphs—including dark grey or red-tinged variations—have been documented in different parts of its range.