The mysterious Holothuria Scabra sandfish , belonging to the sea cucumber family, shares a common anatomical structure with other species within its group Its body is elongated, cylindrical, and somewhat stubby, featuring a dorsal side that exhibits a color spectrum ranging from grey-brown to black. Darkened wrinkles traverse the body, adorned with small black papillae spanning from end to end. The ventral side, in contrast, is lighter and relatively flat. Positioned on this ventral surface, considered the front end, is the mouth, from which feeding tentacles protrude – an attribute typical of sea cucumbers(beach de mer). The sandfish boasts approximately 20 short tentacles for this purpose. At the opposite end, the anus is situated on the dorsal side.
These fascinating creatures can attain an average length of 22 cm, with some individuals growing as large as 40 cm. They reach maturity around 16 cm or 200 grams, with exceptional cases exhibiting weights of up to 500 grams within a single year. While the exact lifespan of undisturbed sandfish remains unknown, it is established that they can survive for at least a decade.
Examining its internal structure, the sandfish reveals its gonads through a single genital orifice located on the dorsal anterior end. The digestive system comprises a mouth, esophagus, stomach, intestine, cloaca, and anus. To facilitate breathing, respiratory trees extend from the cloaca. The thick body wall, constituting 56% of their weight, contains calcareous plates known as spicules, crucial for species identification. Sandfish can exhibit a unique ability shared by sea cucumbers – the capability to eviscerate internal organs under stress and subsequently regenerate them. In the case of sandfish, this regeneration process takes approximately two months.