Box jellyfish
In Australia (mainly northern; however, box jellyfish can live in subtropical waters as far south as Sydney, with "Carybdea marsupialis" being recorded as far south as Bermagui, Sapphire Coast) the highest risk period for the box jellyfish is between October and May, but stings and specimens have been reported all months of the year. Similarly, the highest risk conditions are those with calm water and a light, onshore breeze; however, stings and specimens have been reported in all conditions.
Morbakka virulenta
In common with other jellyfish in the class Cuboza, "Morbakka virulenta" has a box-like shape. It has rabbit like rhopaliar horns and closely resembles its close relative from Australia, "Morbakka fenneri". "M. virulenta" is one of the largest species of box jellyfish, with tentacle lengths of about three metres at maximum extension. The maximum bell height observed in "M. virulenta" can range up to 250 mm and the bell width can range up to 200 mm. The bell of "M. virulenta" is rectangle-shaped and covered with nematocyst warts. "Morbakka virulenta" can be distinguished from other species in the family by its heavily branched velarial canals as well as two rows of perradial warts with additional scattered warts.