FIGURE 4.

Cleared and double‐stained specimen of Astronesthes sp. (MNHN 2000 0576, 118 mm SL) under polarized light (a–c); and histological serial section of Astronesthes niger (MCZ 133101, 62 mm SL). (a) Myoseptum of V25 at 0,45L. ENTB, EPTB and ECT present; (b) zoom on distally forked ECT. (c) Myoseptum of V34 at 0,60L. Distally forked ECT; proximally forked intermuscular with ENTB/EPTB as anteromedial branch and LTB as anterolateral branch. (d) Transverse serial section showing thin horizontal septum. Abbreviations: DAC, dorsal anterior cone; ECT, epicentral tendon; ENTB, epineural tendon bone; EPTB, epipleural tendon bone; HS, horizontal septum; LTB, lateral tendon bone; R, rib; VAC, ventral anterior cone