Euryalidae Gray, 1840

Stöhr, Sabine, Hugall, Andrew F., Thuy, Ben & Martynov, Alexander, 2018, Morphological diagnoses of higher taxa in Ophiuroidea (Echinodermata) in support of a new classification, European Journal of Taxonomy 416, pp. 1-35 : 7

Family Euryalidae Gray, 1840

Type genus

Euryale Lamarck, 1816 (type species: E. aspera Lamarck, 1816 ).

Other genera

Asteromorpha Lütken, 1869 , Asteroschema Örstedt & Lütken, 1856 , Asterostegus Mortensen, 1933 a , Astrobrachion Döderlein, 1927 , Astroceras Lyman, 1879 , Astrocharis Koehler, 1904 , Ophiocreas Lyman, 1869 , Squamophis Okanishi et al. 2011 , Sthenocephalus Koehler, 1898 , Trichaster Agassiz, 1836 .

Diagnosis

Dorsal disc with thickened skin and embedded external ossicles. Single column of teeth, dental plate fragmented. Arms branching in Euryale , Trichaster and Sthenocephalus . Distal vertebrae with oral bridge in Asteromorpha , Asterostegus , Astrobrachion , Astroceras , Euryale , Sthenocephalus and Trichaster ( Okanishi et al. 2011 b) . Gonads may extend into the arms. Arm spine articulation with large muscle opening separated from the nerve opening by a large, swollen ridge.