Astrobrachion adhaerens

Basket stars have extensively branched arms made of a complex system of tissues and muscles. These arms are capable of regeneration, which is a characteristic that likely evolved as a response to frequent breaks of their long, thin, and fragile arms.^[10]

Genera in Euryalida typically have thick skin and possess lateral arm plates but rarely have ventral arm plates or dorsal arm plates.^[11] The genus Astrobrachion is set apart by having small ventral plates separated from the lateral arm by a supportive dermal tissue layer.^[8]

The length of arm spines on Astrobrachion is the same length as the corresponding arm segment, like its sister genus Squamophis. These two genera, therefore, have the shortest spines in the Asteroschematidae family.^[7]

Astrobrachion adhaerens has longitudinal stripes while its sister species A. constrictum has transverse color banding on the arms. Both species vary from red to yellowish-white in color.^[8]

Little is known of the reproductive system of A. adhaerens, but sexual characteristics are likely shared with closely related A. constrictum. A. constrictum are dioecious and exhibit no sexual dimorphism. They have a fused bursae and long, tubular gonads in the proximal half of their arms. Somewhat unique^{[clarification needed]} to reproduction within species of the Asteroschematidae family is the structure of the germinal epithelium: folding over the testes in the male and concentric tapering of the germinal epithelium in the ovaries in the female.^[4]

Very little of A. adhaerens behavior has been observed as their hard substrate, nocturnal activities and deep water habitat hinder the observation and collection of specimens.^[3][4] A. adhaerens are suspension feeders that unfold their long, thin arms to feed at night.^[5]