Info
A distinction between males and females is not externally recognizable. Maturity is reached at a body length of about 16 cm. Spawning occurs mainly in summer and fall, although in equatorial waters spawning occurs throughout the year.
Holothuria atra can also reproduce cross splitting.It is usually smaller individuals that split in this manner.A constriction occurs, becomes deeper and deeper and after some time the skin separates leaving two relatively wide but short small sea rollers. No sand adheres to the newly separated areas because there are no tube feet to hold the grains.
Lissocarcinus orbicularis, a small crab, is known to live in a commensal relationship on this species.
Although the black sea cucumber does not have Cuvier's tubes, it can still release holothurin, which is toxic to fish, and must therefore be handled with care.
Synonyms:
Halodeima atra (Jaeger, 1933)
Holothuria (Halodeima) atra amboinensis Théel
Holothuria (Holothuria) atra Jaeger, 1833
Holothuria (Microthele) affinis Brandt, 1835
Holothuria amboinensis Semper, 1868
Holothuria radackensis Chamisso & Eysenhardt, 1821
Holothuria sanguinolenta Saville-Kent, 1893
Sea cucumbers of the family Holothuriidae possess, exceptions confirm the rule, so-called Cuvier's tubes (named after the French naturalist Georges Cuvier, * August 23, 1769 † May 13, 1832).
These are long, thin tubes that are located on the rectum of the echinoderms and are flung towards potential predators for defense.
These released tubes form a sticky, tough and stretchy network in which fish, crustaceans or other prey predators can become entangled.
The adhesives may also contain toxins (holothurin).
Sea cucumbers are the vacuum cleaners of the oceans, continuously cleaning the sea floors, so it may be useful for aquarists to keep one or more sea cucumbers in the aquarium to avoid detritus rich zones.
Problem:
Many sea cucumbers of the family Holothuriidae can release their venom into the aquarium water when they are in danger or dying, corals are mostly not harmed by the venom, but fish usually die.
Holothurins can cause severe, burning pain when in contact with the skin and irritation and even blindness when in contact with the eyes. When ingested systemically, the toxins can cause paralysis, muscle spasms, and discomfort in the digestive system, and in larger quantities, death by respiratory paralysis.
Since sea cucumbers are considered a delicacy in many Asian countries, the Cuvier's tubes containing the toxins must be removed before preparation or consumption.