Astrophiuridae Sladen, 1879

Goharimanesh, Mona, Stöhr, Sabine, Mirshamsi, Omid, Ghassemzadeh, Fereshteh & Adriaens, Dominique, 2021, Interactive identification key to all brittle star families (Echinodermata; Ophiuroidea) leads to revised morphological descriptions, European Journal of Taxonomy 766 (1), pp. 1-63 : 24

Family Astrophiuridae Sladen, 1879

Type genus

Astrophiura Sladen, 1879 .

Other genera

Ophiomisidium Koehler, 1914 ; Ophiophycis Koehler, 1901 .

Description

ARM.Arm shape unbranched; length less than 2× disc diameter; covering without granules/spines/tubercles. Arm combs absent. Dorsal arm plate present.Accessory dorsal arm plate absent. Ventral arm plate present. Accessory ventral arm plate absent. Girdle of tiny hooks on the arms absent. Spines all similar in shape. Arm spine cross section round. The ratio of thickness of distal ⅓ of arm spine to maximum thickness (in a given cross-sectional plane) 0.6–0.9, or 0.9–1. Arm spines cylindrical or pointed; mainly lateral; predominantly parallel to arm axis (adpressed). Longest arm spines shorter than half a segment. Tentacle scales present; pores visible only on proximal arm; nearly as long as wide; as long as the spine nearby; cross section oval. Position of lateral arm plate (LAP) only lateral. Dorsal and/or ventral edge(s) of LAPs without constriction. Ventral position of LAP not projecting ventro-proximalwards. Ventro-distal tip of LAP not projecting ventralwards. Arm spine articulation without dorsal and ventral lobes, or with dorsal and ventral lobes; without sigmoidal fold; arranged over entire distal LAP edge; all similar. Distance between spine articulations equal. Nerve and muscle openings separated by small ridge if at all.

DORSAL DISC. Disc circular; high (above arm level). Integument not obscuring plates. Dorsal disc without granules; with obvious primary plates; without scales or with a few scales ( O’Hara et al. 2018); without spines. Dorsal disc scale/plate without tubercles. Radial shield present; without granules/spines; length between one third and half of the disc radius; scalene (oblique) triangular.

VENTRAL DISC. Gonads restricted to the disc. Ventral interradii without granules/spines. Scales on ventral interradii absent. Ventral teeth several (tooth papillae). Infradental papillae on oral plate present. Buccal scales on OP present. Accessory oral papillae on OP absent. Lateral oral papillae on OP present; single row of lateral papillae; block-shaped and spiniform.Adoral shield spine present. Lyman’s ossicle absent. Oral shield covering less than one third of interradius; much wider than long. Madreporite no data. Adoral shield meeting in front of the oral shield. Abradial genital plate not twisted. Number of genital slits one per bursa. Genital slit longer than half the length of an interradius. Genital papillae absent. Dental plate and teeth no data.

VERTEBRAE. Vertebrae zygospondylous; beyond segment 5 with short keel; without oral bridge.