FREQUENTLY on social media, photos of a type of box jellyfish in Moreton Bay or offshore are posted and shared.
The animal photographed is the Morbakka jellyfish. It is also known as the Fire Jelly or Moreton Bay Stinger.
It is not the same species as the “true” box jellyfish, that is typically found further north, but which is slowly moving its distribution further south.
The Morbakka has been found as far south as Sydney and generally prefers offshore waters but stings requiring medical treatment are known from Moreton Bay, including western Moreton Bay. It is frequently found around Redcliffe.
The Morbakka belong to a group of animals called the Cubozoa and there are about 50 species in the group.
This group of jellyfish are very different from the typical jellyfish you see floating around Moreton Bay. The body or as it is called the bell, of the Morbakka is between 6 and 18 centimetres long with 4 ribbon like tentacles that can be a metre long.
Very little is known specifically about Morbakka, but the general biology of the group is well studied. Cubozoa have very well-developed eyes – many of them!
The box jellyfish has 24 eyes that do not form images but detect light and dark. Cubozoa actively hunt their prey while typical jellyfish do not. All Cubozoa have nematocysts – specialised stinging cells that contain tiny, barbed harpoons and transfer venom.
The sting of a Morbakka jellyfish can cause Irukandji syndrome - a collection of symptoms that include severe lower back pain, nausea and vomiting, breathing difficulties, profuse sweating, severe cramps and spasms and a feeling of impending doom. If you are stung or suspected of being stung urgently seek medical treatment.
The good news is that unlike the box jellyfish, no fatalities have been recorded.