Microscopic (A), µCT volume rendered (B) and surface rendered (C, D) images of basal part of arm (7–13th arm segments) of Asteronyx loveni (NSMT E-5638). Oral view. Upper and lower sides indicate distal and basal orientation, respectively. Oral side is virtually dissected in D Inter-vertebral muscles are colored purple in D Black arrow heads in B and D indicate identical vertebra, and ST and AS labels also indicates the identical characters in A, B and C. Abbreviations: ASP, arm spine; LAP, lateral arm plate; ST, secondary teeth.