Holothuria sanctori is a species belonging to the Holothuridae family, which in turn is included in the Holothuriida order and is in the Holothuroidea class. This species is found in the waters of the Mediterranean Sea as well as in the eastern Atlantic Ocean waters. It tends to be located in nooks and crannies of the rocky bottom in shallow and relatively warm waters where there is a tendency to accumulate sediment and occasionally in Posidonia oceanica meadows.
The body of Holothuria sanctori is cylindrical and elongated, presenting on the dorsal surface numerous conical papillae that are distributed irregularly and whose apices are very intense brown or even black. The largest specimens recorded reach 30 cm in length. The body is brown, and there are rounded spots of much lighter coloration, which correspond to the bases of the papillae.
Holothuria sanctori is a limnivorous feeding species, that is to say that using the 20-22 tentacles that surround the mouth, they collect the sediment and filter the organic particles from it. The organic particles are digested, while the sand particles and other non-digestible materials are mixed with a mucous secretion, to expel them forming sand cords.
Dioecious species, there are Holothuria sanctori specimens of both sexes, although there is no differentiation to distinguish them (no sexual dimorphism). After the release into the water column of the gametes of the specimens of both sexes, external fertilization occurs, thus forming the larvae that will pass a planktonic phase and after several stages, descend to the bottom of the sea and undergo a metamorphosis that turns them into juveniles.
It should also be noted that Holothuria sanctori has Cuvier’s glands, structures characteristic of certain holothurids that are used as a form of defense and through which they release whitish-pinkish and very sticky filaments to disconcert possible predators before their attacks.
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