As expected, both chitin and calcium carbonate are the most representative compounds in the construction of the cuticle layers in S. serrata
throughout the molt cycle. The mirror images with GAG peak and chitin depression in the
cuticle at A stage indicate that the GAG increase represents an initial mineral nucleation period. In
S. serrata the organic fraction of new cuticle forms from the D2 stage while mineralisation
occurs primarily during ecdysis.