Key facts about Sea cucumbers

Sea cucumbers are marine animals that belong to the class Holothuroidea, which is part of the phylum Echinodermata.

Key facts about Sea cucumbers
Table of Contents

About Sea cucumbers:

  • Sea cucumbers are marine animals that belong to the class Holothuroidea, which is part of the phylum Echinodermata.
  • They are found in saltwater environments worldwide, primarily on or near the seabed, and are characterized by their soft, leathery skin and elongated bodies.
  • Sea cucumbers are the janitors of tropical seas.
    • Just as a vacuum cleaner consumes dirt and fills up its bag, sea cucumbers consume bacteria and decaying organics from the seafloor and convert this into sea cucumber body mass, reducing the “food” available to support the growth of microbial pathogens.

Appearance and Habitat:

  • Size and Colors: Sea cucumbers come in various sizes, ranging from 0.75 inches to 10 feet long, and display a wide array of colours, including brown, red, orange, yellow, white, blue, and patterns.
  • Body Structure: They have bumps on their bodies and lack eyes and a brain but have evolved clever ways to navigate, defend themselves, and forage for food.
  • Threat: Sea cucumbers are preyed upon by various marine animals and are also consumed by humans. Overfishing is a significant threat to their populations, with more than 70 species being exploited for profit.

Symbiotic Relationship: Some species of sea cucumber have a symbiotic relationship with the star pearlfish, which uses the sea cucumber’s body as shelter.


Q1: What are echinoderms?

Echinoderms are named for the spines or bumps covering the outer surface of the bodies of many of them. Examples of echinoderms include sea stars, sea urchins, sea cucumbers, brittle stars, and feather stars (Fig. 3.83). Although they may appear very different, echinoderms all have two major defining characteristics that set them apart from all other animals: a water vascular system and five-sided radial symmetry.

Source: Coral reef recovery could get a boost from an unlikely source: Sea cucumbers, the janitors of the seafloor

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