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Keesingia gigas was discovered and determined by Dirk Hartog, Shark Bay and the Ningaloo Reef on the west coast of Australia.
Irukandji jellies are of increasing concern as their stings are being reported more and more frequently around the world. So far, only two species from Western Australia were known, namely Carukia shinju Gershwin, 2005 and Malo maxima Gershwin, 2005, both from Broome.
Two new species
that are thought to cause the Irukandji syndrome have recently been found and are described here. One, Malo bella, comes from the Ningaloo Reef and Dampier Archipelago regions. It differs from its relatives in its small size at maturity, its statolith shape, irregular warts on the perradial lobes and a unique combination of other features described here.
This species is not associated with any particular stings, but its phylogenetic relationship suggests that it may be highly toxic.
The second species, Keesingia gigas, is found in the Shark Bay and Ningaloo Reef regions. This enormous species is unique in having key features of three families, including crescent-shaped phacelles and broad-winged pedalia (Alatinidae), and deeply incised rhopal niches and feather-like protuberances of the velarial canals (Carukiidae and Tamoyidae). With these two new species, the number of known or suspected causes of the Irukandji syndrome increases to at least 16.
Research into the biology and ecology of these species should be a high priority in order to manage their potential impact on public safety.
The moon jellyfish belongs to the cubed jellyfish and feeds predatory on zooplankton, which it captures with the help of its long tentacles and the stinging cells located there, and kills extremely quickly.
Box jellyfish kill more people each year than sharks, rays and sea snakes combined, with around 100 people dying each year from jellyfish stings.
The venom of moon jellyfish is produced by structures in the post-Golgi vesicles of the nematocysts.
When the tentacles come into contact with prey or potential predators, a venom cocktail is quickly released from the nematocysts via a long spiny tube, rendering the target organism immobile.
Most box jellyfish live in coastal waters, but Alatina is unusual in that specimens have also been collected in the open ocean at great depths.
Alatina is notable in that populations form monthly aggregations to mate in conjunction with the lunar cycle.
Encounters between humans and this box jellyfish result in very, very painful and burning injuries for bathers or swimmers, as batteries of stinging cells inject a highly potent cell toxin into human skin.
So far, no deaths have been reported from this type of box jellyfish, but the affected skin areas should be cooled as quickly as possible and sprinkled with diluted vinegar.
It is strongly recommended to consult a doctor if the injuries are extensive.
Combined molecular and morphological analyses of the venomous moon jelly Alatina alata suggest that the gastric cirri contain glandular cells that may play a dual role in the secretion of toxins and toxin-like enzymes.
These putative glandular cells could be important for cubozoans both internally (digestion of prey) and externally (poisoning).
Despite the absence of nematocysts in the gastric cirri of mature Alatina alata medusae, this area of the digestive system appears to be the region of the body where venom-implicating gene products are found in the greatest abundance, challenging the notion that in Cnidaria venom is synthesized exclusively in or near nematocysts.
Victims developed the Irukandji syndrome.
Color: The bell is transparent and colorless, somewhat cloudy appearance, with orange exumbrellar nubs, mesenteries and pedalial canals whitish.
Nematocysts: could not be found on the bell nubs or pedalia.
Etymology: The species name “gigas” refers to the enormous size of this species.
Irukandji jellies are of increasing concern as their stings are being reported more and more frequently around the world. So far, only two species from Western Australia were known, namely Carukia shinju Gershwin, 2005 and Malo maxima Gershwin, 2005, both from Broome.
Two new species
that are thought to cause the Irukandji syndrome have recently been found and are described here. One, Malo bella, comes from the Ningaloo Reef and Dampier Archipelago regions. It differs from its relatives in its small size at maturity, its statolith shape, irregular warts on the perradial lobes and a unique combination of other features described here.
This species is not associated with any particular stings, but its phylogenetic relationship suggests that it may be highly toxic.
The second species, Keesingia gigas, is found in the Shark Bay and Ningaloo Reef regions. This enormous species is unique in having key features of three families, including crescent-shaped phacelles and broad-winged pedalia (Alatinidae), and deeply incised rhopal niches and feather-like protuberances of the velarial canals (Carukiidae and Tamoyidae). With these two new species, the number of known or suspected causes of the Irukandji syndrome increases to at least 16.
Research into the biology and ecology of these species should be a high priority in order to manage their potential impact on public safety.
The moon jellyfish belongs to the cubed jellyfish and feeds predatory on zooplankton, which it captures with the help of its long tentacles and the stinging cells located there, and kills extremely quickly.
Box jellyfish kill more people each year than sharks, rays and sea snakes combined, with around 100 people dying each year from jellyfish stings.
The venom of moon jellyfish is produced by structures in the post-Golgi vesicles of the nematocysts.
When the tentacles come into contact with prey or potential predators, a venom cocktail is quickly released from the nematocysts via a long spiny tube, rendering the target organism immobile.
Most box jellyfish live in coastal waters, but Alatina is unusual in that specimens have also been collected in the open ocean at great depths.
Alatina is notable in that populations form monthly aggregations to mate in conjunction with the lunar cycle.
Encounters between humans and this box jellyfish result in very, very painful and burning injuries for bathers or swimmers, as batteries of stinging cells inject a highly potent cell toxin into human skin.
So far, no deaths have been reported from this type of box jellyfish, but the affected skin areas should be cooled as quickly as possible and sprinkled with diluted vinegar.
It is strongly recommended to consult a doctor if the injuries are extensive.
Combined molecular and morphological analyses of the venomous moon jelly Alatina alata suggest that the gastric cirri contain glandular cells that may play a dual role in the secretion of toxins and toxin-like enzymes.
These putative glandular cells could be important for cubozoans both internally (digestion of prey) and externally (poisoning).
Despite the absence of nematocysts in the gastric cirri of mature Alatina alata medusae, this area of the digestive system appears to be the region of the body where venom-implicating gene products are found in the greatest abundance, challenging the notion that in Cnidaria venom is synthesized exclusively in or near nematocysts.
Victims developed the Irukandji syndrome.
Color: The bell is transparent and colorless, somewhat cloudy appearance, with orange exumbrellar nubs, mesenteries and pedalial canals whitish.
Nematocysts: could not be found on the bell nubs or pedalia.
Etymology: The species name “gigas” refers to the enormous size of this species.
