squamation

noun3

1. •
   The condition or character of being covered with scales.

   • A Palaeoniscoid fish showing a condition of squamation almost identical with that of Polyodon. — 1881
2. •
   A particular arrangement of scales; a special mode or form of squamation.

   • A fish from the Muschelkalk…has been made the type of the genus Prohalecites on account of peculiar features in its squamation. — 1889
3. •
   A scaly growth on the skin.