1. Axial Muscles

2. Skeletal of trunk and tail
hypobranchial
tongue
extrinsic muscles of eye

3. Metamerism Origins in mesodermal somites

4. Fish Axial muscles consist of myomeres separated by myosepta
Except in agnathans these are divided into dorsal (epaxial) and ventral (hypaxial) masses by the horizontal skeletogenous septum
Metamerism is interrupted by pelvic and pectoral girdles. Dorsal to gills are epibranchials; beneath gills hypobranchials

5. Tetrapods Most metamerism lost due to locomotion
Amniotes develop strap-like or pinnate epaxials above the transverse process (TP).
Similar arrangements beneath TP allow greater flexibility.

6. Epaxials of trunk:
from base of skull to tail
called dorsalis trunci in amphibians
4 groups in amniotes -
Intervertebrals
Longissimus
Spinales
Iliocostales

8. Hypaxials of trunk:
Subvertebrals (quadratus lumborum and psoas)
Oblique and transverse
Rectus

9. Hypobranchial and Tongue Muscles
Mesenchyme of postbranchial somites move forward in floor of pharynx (ant. extensions of hypaxial muscles)