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Euryalids are the least well known Ophiuroids. There is even lesser knowledge about A. adhaerens available. However it is closely related to its only sister species, A. constrictum and information about the sister species and family as a whole can provide insight into A. adhaerens.

Anatomy and Morphology
Basket stars have branched arms made of a complex system of tissues and muscles capable of regeneration. Regenerative abilities have likely evolved as an evolutionary response to breaking their long, thin and fragile arms. A. adhaerens are suspension feeders that feed at night by unfolding their branched arms.

Euryalidae have thick skin and possess lateral arm plates but rarely ventral arm plates and dorsal arm plates. The genus Artrobrachion however has small ventral plates that are separated from the lateral arm by a supportive well-developed dermal tissue layer.

The genus Astrobrachion has epidermal ossicles (superficial body ossicles), differentiating it from its sister genera Astrocharis which has plate-shaped epidermal ossicles. The length of arm spines on Astrobrachion is the same length as the corresponding arm segment and is hence the shortest in the genera.

A. adhaerens has longitudinal stripes while its only sister species A. constrictum has transverse colour banding on the arms. Both species vary from red to yellowish-white in colour.

A. adhaerens likely to share certain sexual characteristics with their sister species, A. constrictum. A. constrictum are dioecious and exhibit no sexual dimorphism. They have a fused burasae and long, tubular gonads that extend into the proximal half of the arms.

Distribution and Habitat
The genus Astrobrachion was first identified in New Zealand. Sister genera were identified in the Caribbean and Philippines.

A. adhaerens is found in the tropical regions of Australia, ranging from Albany, Western Australia and the northern Australian coast to New South Wales, Lord Howe Islands and the Kermadec Islands. The species is allopatric except at Lord Howe Island.

Basket stars are found to reside on soft, cold water-corals such as the Nephtheidae soft corals at depths ranging from 25m to 1317m, especially on the Labrador, Newfoundland and Baffin Bay shelves. However the relative co-occurrence ranges between 54% and 4%, suggesting that soft corals are not a necessary basket star habitat.

Behaviour
The genus Astrobrachion likely exhibits activity at night in deep waters and hence behaviour has not been observed. Also, their hard substrate and epizoic habitat hinders the collection of specimens.

Taxonomy
Eurylaid fossils date back to strata as young as Cretaceous and Neogene. In the past, the order Euryalida was thought to differ significantly from other orders within the class, resulting in the class being divided into euryalids and non-euryalids. However, recent studies have found that Euryalids diverged from during the Triassic periods and thus share the morphologies of the class Ophiurids.