Variability of the scutes of the turtle shell: mechanisms of morphogenesis and the nature of anomalies

Abstract

The morphogenesis of the horny scutes in turtle shell was studied. It was shown that the position of the scute rudiments (epidermal placodes) is determined by somatic segmentation of the turtle embryo. It was found that scute rudiments are formed exclusively in the areas of septal depressions — in places where transversal miosepta attached to the skin. Intraspecific variability of folidosis due to the presence of free septal depressions that can “fill” extraordinary placodes. These aberrations have a high frequency and, as a rule, lead to asymmetry of folidosis. Refs 10. Figs 1.