Snake Sea Cucumber

Synapta maculata, commonly known as the snake sea cucumber, is a sea cucumber species belonging to the family Synaptidae. It can be found in the shallow waters of the tropical 🌊 Indo-Pacific Ocean. With a potential length of up to 3 meters (10 feet), it ranks among the longest sea cucumbers in the world.

Synapta. maculata is characterized by its slender body, extending up to approximately 2 meters (7 feet). While not the heaviest or bulkiest sea cucumber, it holds the distinction of being one of the longest, with occasional individuals surpassing 3 meters (10 feet). The species exhibits variability in coloration, typically featuring yellowish-brown hues with wide longitudinal stripes and patches of darker shades. The body wall is supported by large anchor-shaped ossicles, microscopic calcareous spike-like structures, measuring up to 2 mm in length. These adhesive ossicles make detachment from a wetsuit a challenging task.

This species is native to the tropical western Indo-Pacific region. It inhabits depths of approximately 20 meters (66 feet) and can be found on reefs, soft sediments, seagrasses, and seaweed-coveundefinedbeds. Synapta maculata is also capable of burying itself under rubble.

The fifteen tentacles of Synapta maculata envelop the mouth and serve as feeding appendages on the surface. These tentacles, extending to about 2.5 cm (1 inch), consist of a short stem and a feather-like blade containing thirty to forty pairs of pinnules. The adhesive outer surfaces of the tentacles feature numerous bulges, while the inner surfaces are smooth and have cilia clusters on the proximal parts. The tentacles engage in continuous motion, pressing against the substrate or seagrass leaf blades to collect food particles through adhesion. They then bend inward until the tips reach the mouth, where the buccal sphincter muscle scrapes off the food. This entire process occurs within seconds, with multiple tentacles delivering their loads simultaneously. In response to disturbances, the tentacles can retract into the pharynx, but they swiftly reemerge to resume particle collection. This species possesses vesicular cells on the outer surface of the tentacles and scattered vesicles on the body surface with an unclear function. It is postulated that these cells may contain a defensive noxious substance. While vulnerable to predation by fish, the unappetizing taste allows the sea cucumber to spend more time feeding without constant tentacle retractions. Additionally, cup-shaped structures near the stem of the tentacles may serve as rudimentary sensory organs to assess the edibility of transported food materials. Synapta maculata demonstrates a defensive mechanism of autotomy, in which larger individuals shed rear sections, while smaller individuals fragment into multiple pieces. Two novel triterpene holostane glycosides with varying anti-tumor activity have been isolated from Synapta maculata.