Fig. 3 in Interactive identification key to all brittle star families (Echinodermata; Ophiuroidea) leads to revised morphological descriptions

Fig. 3. SEM images of various ossicle structures in brittle stars. A. Muscle and nerve opening on LAP separated by small ridge if at all (Amphiura chiajei Forbes, 1843). B. Muscle and nerve opening on LAP separated by large, prominent ridge or regular stereom (Ophiolycus purpureus (Düben & Koren, 1846)). C. Non-keeled vertebra (Amphiura chiajei). D. Keeled vertebra (Ophiothrix fragilis Abildgaard, 1789). E. Vertebra with oral bridge (Euryale aspera Lamarck, 1816). F. Sockets indicate teeth and tooth papillae on dental plate as single row (Amphilepis norvegica (Ljungman, 1865)). G. ½ single row of teeth and ½ tooth papillae (Ophiothrix fragilis). H. ⅔ single row of teeth and ⅓ tooth papillae (Ophiocamax vitrea Lyman, 1878). I. Sockets on dental plate covering evenly (Asteronyx loveni Müller & Troschel, 1842). J–K. LAP not arched = position lateral. L. LAP arched = wrapped around the arm.