Phyllorhiza punctata
Phyllorhiza punctata is a species of jellyfish, also known as the Australian spotted jellyfish
or the white-spotted jellyfish. It is native to the southwestern Pacific, where it feeds primarily
on zooplankton. P. punctata average 45–50 centimetres (18–20 in) in bell diameter but in October
2007, one 72 cm (28 in) wide, perhaps the largest ever recorded, was found on Sunset Beach,
North Carolina.
or the white-spotted jellyfish. It is native to the southwestern Pacific, where it feeds primarily
on zooplankton. P. punctata average 45–50 centimetres (18–20 in) in bell diameter but in October
2007, one 72 cm (28 in) wide, perhaps the largest ever recorded, was found on Sunset Beach,
North Carolina.
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[edit]Description
True jellyfish go through a two-stage life cycle which consists of a medusa stage (adult) and a polyp
stage (juvenile). In the medusa stage male jellyfish release sperm into the water column and the female
jellyfish gathers the sperm into her mouth where she holds the eggs. Once fertilizationoccurs and
larvae are formed they leave their mother and settle to the ocean floor. Once on the bottom a polyp form
occurs and this formreproduces asexually by “cloning” or dividing itself into other polyps. Jellyfish can
live for up to five years in the polyp stage and up to two years in the medusa stage.
stage (juvenile). In the medusa stage male jellyfish release sperm into the water column and the female
jellyfish gathers the sperm into her mouth where she holds the eggs. Once fertilizationoccurs and
larvae are formed they leave their mother and settle to the ocean floor. Once on the bottom a polyp form
occurs and this formreproduces asexually by “cloning” or dividing itself into other polyps. Jellyfish can
live for up to five years in the polyp stage and up to two years in the medusa stage.
When found in warm waters these jellyfish flourish. They are mostly euryhaline but low salinities may
have a negative effect on the species. In times of low salinity these jellyfish exhibit loss of their
zooxanthellae.[1]
have a negative effect on the species. In times of low salinity these jellyfish exhibit loss of their
zooxanthellae.[1]
They have only a mild venom and are not considered a threat to humans. They has a mild or non-noticeable
sting which can be cured with vinegar. Salt water can be used as a last resort.
sting which can be cured with vinegar. Salt water can be used as a last resort.
[edit]Invasive species
The species has been found in the waters off the Hawaiian Islands since at least 1945,[2] Since at least
2000, Phyllorhiza punctata has been found in large numbers in Gulf of Mexico.[3] While it is not known
how it was introduced to the region, it has been theorized that budding polyps may have attached
themselves to ships,[4] or gotten carried in a ship's ballast tank which was subsequently dumped in
the Gulf.[5] As an invasive species, it has become a threat to several species ofshrimp. In Gulf waters,
the medusae grow to unusually large size, upwards of 60 cm (24 in) across.
2000, Phyllorhiza punctata has been found in large numbers in Gulf of Mexico.[3] While it is not known
how it was introduced to the region, it has been theorized that budding polyps may have attached
themselves to ships,[4] or gotten carried in a ship's ballast tank which was subsequently dumped in
the Gulf.[5] As an invasive species, it has become a threat to several species ofshrimp. In Gulf waters,
the medusae grow to unusually large size, upwards of 60 cm (24 in) across.
In July 2007 smallish individuals were seen in Bogue Sound much further north along the North Carolina
coast. However, their ability to consume plankton and the eggs and larvae of important fish species is
cause for concern. Each jellyfish can filter as much as 50,000 litres (13,000 US gal) of seawater per day.
While doing that, it ingests the plankton that native species need.
coast. However, their ability to consume plankton and the eggs and larvae of important fish species is
cause for concern. Each jellyfish can filter as much as 50,000 litres (13,000 US gal) of seawater per day.
While doing that, it ingests the plankton that native species need.
It has also been spotted off the Southern California coast, but its presence there has not yet been confirmed.[4]
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[edit]References
- ^ Masterson, J. (2007-06-13). "Phyllorhiza punctata". Smithsonian Marine Station at Fort Pierce. Retrieved 2012-05-28.
- ^ "Phyllorhiza punctata, Introduced Marine Species of Hawaii Guidebook". Bishop Museum. 2002. Retrieved 2012-05-28.
- ^ "Phyllorhiza punctata (‘spotted jellyfish’)". Dauphin Island Sea Lab. Retrieved 2012-05-28.
- ^ a b "Spotted Jellyfish (Phyllorhiza punctata)". Elkhorn Slough National Estuarine Research Reserve. Retrieved 2012-05-28.
- ^ "White-spotted Jellyfish Fact File". Australian Museum. 2009. Archived from the original on 2009-07-13.
[edit]External links
- Invasion of the Jellies, California Academy if Sciences
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