Ophiocanops fugiens
Encyclopedia
Ophiocanops fugiens is the only one living species in the brittle star
Brittle star
Brittle stars or ophiuroids are echinoderms in the class Ophiuroidea closely related to starfish. They crawl across the seafloor using their flexible arms for locomotion. The ophiuroids generally have five long slender, whip-like arms which may reach up to in length on the largest specimens...

 family Ophiocanopidae. It has been regarded as the most primitive brittle star, close to paleozoic
Paleozoic
The Paleozoic era is the earliest of three geologic eras of the Phanerozoic eon, spanning from roughly...

 forms, though other authors have disagreed with the view. Ophiocanops is usually placed in the order Oegophiurida
Oegophiurida
Oegophiurida is an order of Ophiuroidea.The physical characteristics of this order include well separated lateral plates, which exposes the oral surface of radial ossicles. It also has vertebrae with streptospondylous articulation, which thus allow for vertical and horizontal movements. The order...

 (suborder Zeugophiurina
Zeugophiurina
Zeugophiurina is a suborder of primitive brittle stars with three extinct families. The family Ophiocanopidae with only one living genus and species, Ophiocanops fugiens has been placed here but recent studies have challenged this classification....

) or regarded as a genus incertae sedis
Incertae sedis
, is a term used to define a taxonomic group where its broader relationships are unknown or undefined. Uncertainty at specific taxonomic levels is attributed by , , and similar terms.-Examples:*The fossil plant Paradinandra suecica could not be assigned to any...

or even given its own subclass
Class (biology)
In biological classification, class is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, order, family, genus, and species, with class fitting between phylum and order...

 Oegophiuridea. Some recent data suggest its relationship to the extant family Ophiomyxidae (it would thus belong to the order Phrynophiurida
Phrynophiurida
Phrynophiurida is an order of brittle stars containing Basket stars.-Characteristics:Phrynophiurida have bursae for as exchange and excretion. Their ventral arm shields are rudimentary, dorsal shields usually absent. Arms sometimes branched, can coil vertically. The vertebrae are joined by...

).

Characteristics

Arms lack dorsal and ventral shields. Madreporite
Madreporite
The madreporite is a lightcolored calcerous opening used to filter water into the water vascular system of echinoderms. It acts like a pressure-equalizing valve. It is visible as a small red or yellow button-like structure, looking like a small wart, on the aboral surface of the central disk of a...

 is on edge of central disc. Digestive glands extend into proximal portions of arms. It has no bursae for gonads and gas exchange/excretion.

Ecology

Ophiocanops fugiens is a rare species found in South Asian seas. Its habitat is shallow water and it lives in association with black coral
Black coral
Black corals are a group of deep water, tree-like corals related to sea anemones. They are also found in rare dark shallow water areas such as New Zealand's Milford Sound where they can be viewed from an underwater observatory. They normally occur in the tropics...

s.
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