Notably, if the glucosamine level is about 72.4% for Cherax in the IM fraction (Table 1C), it remains not negligible in the SM fraction (about 35.8%) [28]. This could be due to the presence of very small chitin fibers (see Figure 3F and G) subdividing the large pocket-like compartments into micro-units framed by larger chitin fibers. Some of these nanometric diameter fibers could be depolymerized and released during the decalcification process, remaining in the supernatant after centrifugation of the decalcifying solution.