Somites are transient segmented structures derived from paraxial mesoderm.

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• Somites are transient segmented structures
  derived from paraxial mesoderm.
• contain the progenitors of the axial skeleton,
  trunk musculature and associated tendons, trunk
  dermis, endothelial cells, and meninges of the
  spinal cord

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• ventromedial part of the somite forms the
  sclerotome
• the remainder of the somite consists of a dorsal
  epithelial layer called the dermomyotome
• dermomyotome quickly separates into two
  structures a dermatome and a myotome The
  dermatomes contribute to the dermis (including
  fat and connective tissue) of the neck and the
  back.

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• The myotomes differentiate into myogenic
  (muscle-producing) cells
• Each myotome splits into two structures a dorsal
  epimere and a ventral hypomere
• The epimeres give rise to the deep epaxial
  muscles of the back, including the erector spinae
  and transversospinalis groups.

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• The hypomeres form the hypaxial muscles of the
  lateral and ventral body wall in the thorax and
  abdomen intercostal muscles,external oblique,
  internal oblique, and transversus abdominis, and
  the rectus abdominis

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• Cervical regionhypaxial myoblasts form the strap
  muscles of the neck, including the scalene and
  infrahyoid muscles.
• Lumbar region, the hypomeres form the quadratus
  lumborum muscles.
• At limb-forming levels, hypaxial myoblasts invade
  the developing limb buds and give rise to the
  limb musculature.

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