These creatures can cause discomfort but most are not lethal.
Common Marine Stingers
Appearance: Air-filled sack usually 3-4 cm and up to 10 cm in length.
A long (usually single) tentacle underneath. This may contract to a few centimetres, or extend to over a metre in length.
Appearance: Mushroom shaped bell 5-30 cms in diameter. No tentacles, but up to eight “fronds” or “frills” hanging underneath.
They are usually found in sheltered bays where the sea floor slopes gradually and near sandbanks at high tide.