Radiography of the anterior part of a Cherax quadricarinatus specimen at the end of the calcium storage process, which occurs all during the premolt, showing the localization of two X-ray dense gastroliths. B: Gastroliths (light microscopy) from Orconectes limosus, at left, and from Cherax quadricarinatus, at right. The macrostructural aspect is similar. The difference of size is proportional to the size of adult specimens of the two species. The flat or slightly concave side on the stomach lumen side
is shown. C–D: Broken gastroliths from Cherax quadricarinatus showing the semispherical
and internal aspect of a gastrolith. C: the flat disc visible in the center
corresponds to the oldest part of the gastrolith, i.e. the beginning of the calcium storage. D:
The homogeneous dense and striated internal structure is well visible on this cross-section.