Chironex fleckeri

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Chironex fleckeri
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Chironex fleckeri

Systematics
Trunk : Cnidarians (Cnidaria)
Class : Box jellyfish (Cubozoa)
Order : Chirodropida
Family : Chirodropidae
Genre : Chironex
Type : Chironex fleckeri
Scientific name
Chironex fleckeri
Southcott , 1956

Chironex fleckeri , also known as sea ​​wasp , is a species of box jellyfish (Cubozoa) that is native to the Pacific beaches of northern Australia and is feared because of its poison. In order to protect yourself from the animals, entire beaches in Australia are fenced in at the seaside or you can go into the water wearing a hive-proof diving , surfing or jellyfish protective suit .

The sea wasp is also used to describe some related species of the family with comparable, but mostly somewhat weaker, poisonous effects, which are not only native to Australia, but also from the beaches of the Pacific to the Philippines and Japan. These were formerly grouped together to form the "type" Chiropsalmus quadrigatus .

features

Light microscope image of nematocytes isolated from the tentacles of Chironex fleckeri (400x magnification)

The sea wasp is the largest box jellyfish species, the largest individuals from Queensland reached an umbrella diameter of 30 centimeters and a fresh weight of 6 kilograms. More typical, however, are individuals with an umbrella diameter of up to about 14 centimeters, which is the maximum size in Western Australia. The bell-shaped, slightly rounded, square screen with a smooth exterior is crystal-clear and transparent and therefore practically invisible in sunlit water. As is typical for box jellyfish, four tentacle-bearing projections called pedalia sit on the screen at the corners of the entire edge of the screen and in between four called rhopalia , which carry most of the sensory organs. The pedals can be moved by muscles and allow the animal a high degree of maneuverability when swimming, which is unusual for jellyfish. The umbrella opening is narrowed by a thin, muscular fold of skin, the velarium, which enables the animal to recoil more precisely and thus swim at high speed. As is typical for the order Chirodropida, each of the claw-shaped Pedalia bears several tentacles, in Chironex up to 15, so a total of 60 tentacles. In the floating medusa, the inside hollow, shoelace-like tentacles are contracted by muscles and then about 5 to 15 centimeters long. When catching prey, they are stretched out and then reach two, possibly up to three meters in length, they are then flat and wide. Inside the tentacles, the pale bluish colored nettle capsules sit in ribbon-shaped zones. Inside the bell-shaped umbrella sits the square stomach stem (manubrium), which is shorter than the umbrella and ends in four lanceolate lips. Inside the animal there is a stomach space from which four gastric pockets branch off on the sides. From these outgoing channels open into an annular channel at the edge of the screen, from which further channels lead into the tentacles and the ropes. The shape of the channels in the Pedalia is the most important characteristic: they run at an obtuse angle, while they are bent at right angles in the genus Chiropsella (which occurs in the same habitat) and in Chironex yamaguchii . The upper gonads protruding into the stomach area are opaque and cock-comb-shaped.

The sea wasp has complex eyesight. Each of the four Rhopalia has six eyes , for a total of 24 eyes. The four outer pigment pits are simply structured and only differentiate between light and dark, the two in the middle have highly developed lenses . The lenses are only a tenth of a millimeter in size and deliver an amazingly sharp image. In addition, there is a sensory organ with a statolith at the base of the rhopalia .

distribution

The species occurs on the north and east coast of Australia, for example from Broome in the west to southern Queensland ( Moreton Bay ). Occurrences on the south coast of New Guinea appear plausible according to ecological requirements, but have not yet been proven with certainty. Information from other waters of Southeast Asia is incorrect, they go back to earlier taxonomic uncertainties (uncertainly delimited species or incorrectly identified individuals).

behavior

Sea wasps live almost exclusively in shallow water near the coast, hardly ever deeper than 5 meters. Many decades of searching, for example in the Great Barrier Reef , only yielded isolated evidence from offshore waters. An investigation of coral reefs in Camden Sound, Kimberley , showed that they can live at least occasionally in water depths of up to 40 meters. The species is a good swimmer and is one of only a few species of jellyfish able to maintain its swimming direction in the face of a differently directed water current. You can achieve high maneuverability even in tight spaces and swim tight turns. The orientation while swimming is at least partially optical, the animals can avoid obstacles, they usually swim actively away from dark silhouettes. The species sometimes takes longer breaks, which have even been interpreted as an occurrence of real sleep , but according to other data, their occurrence does not seem to be mandatory, but depends on the environmental conditions. The species hunts as juvenile crustaceans, especially the shrimp species Acetes australis ( Sergestidae family ), but larger and older medusas with an umbrella diameter of around 6 to 10 centimeters also prey on fish. The typical catching technique for box jellyfish is: The animals swim upwards at high speed and stop with a quick turn. They then sink downwards with widely spread tentacles. If prey gets stuck, the tentacles are shortened by muscle movements and the prey is transported to the ostium . Sea wasps themselves are the prey of numerous species of fish, they also belong to the preferred prey of the green turtle ( Chelonia mydas ).

Poisonous effect

Sea wasp poisoning accidents are a regular occurrence in Australian waters. 63 deaths from the species have been documented for the years 1884 to 1996. Children are often affected and there are more deaths almost every year. Accidents occur in shallow water, in warm, windless weather, when swimmers swim into the tentacles that are almost invisible in the water. Immediately a severe pain reaction occurs ("like with red-hot iron"). Often other areas of skin such as hands and arms are stinged, for example when trying to remove the tentacles sticking to the skin. In the following hours, erythema and edema appear , followed by necrosis of the skin, which leaves permanent scars. Death can occur about five to twenty minutes after the sting.

The poison of the sea wasp has a painful and necrotizing effect on the skin, on muscles (myotoxic), especially the heart muscle (cardiotoxic), on the blood flow and blood vessels ( hemodynamic ) and on the red blood cells ( hemolytic ). For these effects, the poison must pass into the blood vessel system. Various proteins contained in the poison are held responsible for the toxicity. The most important toxins are referred to as CfTX-1 and CfTX-2, they belong to a family of similar proteins that have also been detected in other species of box jellyfish and are probably restricted to these. The active protein is only part of the overall structure, the rest, the so-called pro-part, is probably involved in transporting it to the target and ensuring correct folding. The effective proteins are grouped together to form a common structure, an oligomer ; they act as a pore-forming toxin by perforating the cell membrane. In the meantime, a number of other proteins, some of which have a similar effect, but different specificity, have been detected in the poison.

treatment

An antidote has been available for a number of years; it is manufactured by the Commonwealth Serum Laboratory (Melbourne, Australia) and must be administered intravenously. However, its effect was not found to be satisfactory in all cases. Since the stinging cells take effect immediately and the patient's life is threatened, immediate measures must be taken in any case. The tentacles usually continue to adhere to the victim's skin after the accident and continue to release considerable amounts of poison when they move. Rinsing with water is not possible. Mechanical removal of the tentacles should be attempted, but carries the risk of further stings. However, the heavily calloused palms themselves are relatively well protected.

Until 2005, the treatment was carried out with pressure-fixing bandages to prevent the poison from being distributed via the lymphatic and circulatory systems. This treatment is no longer recommended by health officials because research has shown that the use of bandages to compress tissue provoked the discharge of stinging cells.

The use of vinegar is recommended because vinegar (4-6% acetic acid) permanently deactivates the undischarged nettle cells and prevents them from opening and releasing poison. According to an in vitro study carried out in 2014, vinegar deactivates the stifle cells that have not been discharged, but cells that have already been discharged could be induced to give off some residual toxins that had remained in the cell until then. However, the methods of this study have been criticized by various experts. Despite these concerns, dilute acetic acid is still the recommended treatment. In the meantime, the effect of zinc doses, as zinc gluconate , has been proven as a drug against the toxic effects.

Life cycle

As is typical for all box jellyfish, the sea wasp shows a regular generation change ( metagenesis ) between two life stages, the polyp and the medusa (or " jellyfish "). The species has a one-year cycle, i.e. one generation per year. Free-swimming jellyfish, which pose a threat to swimmers, are registered in Australia from around November to May, reproductive individuals with fully developed gonads in late southern summer to early autumn. The polyp stage of the species develops in coastal waters, especially estuaries , mostly mangrove swamps , regularly under conditions of fluctuating salinity , down to a minimum of about 11 per mille, with even lower levels of up to 5 per mille (during floods of the river) being tolerated for a shorter time. The zygotes and planula larvae floating in the water have a sticky surface and therefore stick to the substrate when washed up on the coast with the tidal current. The planulae are mobile, they can then seek a more favorable place by actively swimming around. Once attached, they develop into a creeping, mobile stage of polyps that does not yet take in food. The already formed nettle capsules serve to protect against predators . If a positive spot, always on a hard substrate, is reached, they transform into the stuck (or sessile), food-consuming polyp stage. As is typical for box jellyfish, the polyp stage is very small, it catches prey (plankton) with the help of its tentacle ring, with each tentacle only having one large nettle capsule at the tip of the arms. These can release further, secondary creeping larvae via asexual budding, which usually settle in the vicinity. Around October to November the polyp changes through a complete metamorphosis into a young medusa. Initially, these barely reach a millimeter in length. They live inside the estuaries during this time.

Taxonomy and systematics

The species was described by Ronald Southcott in 1956 . He had received the species from the Australian doctor and naturalist Hugo Flecker, who had collected it after some initially inexplicable deaths and sent it to him; Southcott named the species in honor of Flecker. The engravings had previously been attributed to the Portuguese galley ( Physalia physalis ), which is a frequent occurrence in swimming accidents on the Australian coasts. The genus Chironex was considered monotypical for a long time until a second species was described in 2009 with Chironex yamaguchii . Together with the (Australian) Chirodectes and (in the Atlantic) Chirodropus they form the family Chirodropidae. The Chiropsalmidae family is probably closely related.

Chironex fleckeri in the film

In the film Seven Lives , Chironex fleckeri is shown as the protagonist's “pet”. He eventually used them for his suicide to donate his heart and cornea . The film shows how painful it can be to touch the deadly jellyfish.

In the episode “ Kur mit Schatten ” in the crime series “ Pfarrer Braun ”, Chironex fleckeri is used as a murder tool, in which the murderer pours a jar with the jellyfish into the bathtub in which the victim is.

supporting documents

literature

  • Marymegan Daly, Mercer R. Brugler, Paulyn Cartwright, Allen G. Collin, Michael N. Dawson, Daphne G. Fautin, Scott C. France, Catherine S. McFadden, Dennis M. Opresko, Estefania Rodriguez, Sandra L. Romano & Joel L. Stake: The phylum Cnidaria: A review of phylogenetic patterns and diversity 300 years after Linnaeus. In: Zootaxa. Volume 1668, pp. 127-182, Wellington 2007, ISSN  1175-5326 ( abstract - PDF ).

Individual evidence

  1. ↑ Peter J. Fenner: The Global Problem of Cnidarian (Jellyfish) stinging. MD Thesis, University of London, 1997. pdf download
  2. ↑ Loisette M. Marsh, Shirley Slack-Smith: Field Guide to Sea Stingers and Other Venomous and Poisonous Marine Invertebrates. Western Australian Museum, 2010. Excerpt from Google Books .
  3. ^ A b Cheryl Lewis, Bastian Bentlage: Clarifying the identity of the Japanese Habu-kurage, Chironex yamaguchii, sp. nov. (Cnidaria: Cubozoa: Chirodropida). In: Zootaxa. Volume 2030, 2009, pp. 59-65 DOI: 10.5281 / zenodo.186248 .
  4. ↑ Sean P. Colin, John H. Costello, Kakani Katija, Jamie Seymour, Kristen Kiefer (2013): Propulsion in Cubomedusae: Mechanisms and Utility. In: PLoS ONE. Volume 8, No. 2, Article e56393, doi : 10.1371 / journal.pone.0056393
  5. ↑ Bastian Bentlage, A. Townsend Peterson, Paulyn Cartwright: Inferring distributions of chirodropid box-jellyfishes (Cnidaria: Cubozoa) in geographic and ecological space using ecological niche modeling. In: Marine Ecology Progress Series. Volume 384, 2009, pp. 121-133, doi : 10.3354 / meps08012 .
  6. ↑ John K. Keesing, Joanna Strzelecki, Marcus Stowar, Mary Wakeford, Karen J. Miller, Lisa-Ann Gershwin, Dongyan Liu: Abundant box jellyfish, Chironex sp. (Cnidaria: Cubozoa: Chirodropidae), discovered at depths of over 50 m on western Australian coastal reefs. In: Scientific Reports. Volume 6, 2015, Article 22290, doi : 10.1038 / srep22290 .
  7. ^ A b c Michael J. Kingsford, Christopher J. Mooney: The Ecology of Box Jellyfish (Cubozoa). Chapter 12 In: KA Pitt, CH Lucas (editors): Jellyfish Blooms. Springer-Verlag, Berlin a. a. 2014, ISBN 978-94-007-7015-7 , doi : 10.1007 / 978-94-007-7015-7_12 .
  8. ↑ Julian L. Kavanau: Is sleep's 'supreme mystery' unraveling? An evolutionary analysis of sleep encounters no mystery; nor does life's earliest sleep, recently discovered in jellyfish. In: Medical hypotheses. Volume 66, No. 1, 2006, pp. 3-9.
  9. ↑ Peter J Fenner & John A Williamson (1996): Worldwide deaths and severe envenomation from jellyfish stings. Medical Journal of Australia 165 (11-12): 658-661. Full text ( Memento from June 30, 1998 in the Internet Archive )
  10. ↑ a b Diane L. Brinkman, James N. Burnell: Biochemical and molecular characterization of cubozoan protein toxins. In: Toxicon. Volume 54, No. 8, 2009, pp. 1162-1173, doi : 10.1016 / j.toxicon.2009.02.006 .
  11. ↑ Diane L. Brinkman, Nicki Konstantakopoulos, Bernie V. McInerney, Jason Mulvenna, Jamie E. Seymour: Chironex fleckeri (Box Jellyfish) Venom Proteins, expansion of a cnidarian toxin family that elicits variable cytolytic and cardiovascular effects . In: Journal of Biological Chemistry . tape 289 , no. 8 , February 21, 2014, p. 4798-4812 , doi : 10.1074 / jbc.M113.534149 , PMID 24403082 .
  12. ↑ Children's Health Queensl: First aid | Queensland Poisons Information Center. In: Children's Health Queensland. Retrieved June 19, 2020 (Australian English).
  13. ↑ Jamie Seymour, Teresa Carrette, Paul Cullen, Mark Little, Richard F. Mulcahy: The use of pressure immobilization bandages in the first aid management of cubozoan envenomings . In: Toxicon: Official Journal of the International Society on Toxinology . tape 40 , no. 10 , October 2002, ISSN  0041-0101 , p. 1503-1505 , doi : 10.1016 / s0041-0101 (02) 00152-6 , PMID 12368122 .
  14. ↑ Robert Hartwick, Vic Callanan, John Williamson: Nematocyst Inhibition in Chironex Fleckeri . In: Medical Journal of Australia . tape 1 , no. 1 , 1980, ISSN  1326-5377 , pp. 15-20 , doi : 10.5694 / j.1326-5377.1980.tb134566.x .
  15. ↑ Philippa Welfare, Mark Little, Peter Pereira, Jamie Seymour: An in-vitro examination of the effect of vinegar on discharged nematocysts of Chironex fleckeri . In: Diving and Hyperbaric Medicine . tape 44 , no. 1 , March 2014, ISSN  1833-3516 , p. 30-34 , PMID 24687483 .
  16. ↑ Should We Stop Using Vinegar To Treat Box Jelly Stings? Not Yet — Venom Experts Weigh In On Recent Study. Retrieved June 19, 2020 (English).
  17. ↑ Jamie E. Seymour: Are we using the correct first aid for jellyfish? In: The Medical Journal of Australia . tape 206 , no. 6 , April 3, 2017, p. 249–250 , doi : 10.5694 / mja17.00053 ( com.au [accessed June 19, 2020]).
  18. ↑ Health Direct Australia: Jellyfish stings. May 29, 2020, accessed June 19, 2020 (Australian English).
  19. ↑ Angel A. Yanagihara, Ralph V. Shohet: Cubozoan Venom-Induced Cardiovascular Collapse Is Caused by Hyperkalemia and Prevented by Zinc Gluconate in Mice. In: PLoS ONE. Volume 7, No. 12, 2012, Article e51368, doi : 10.1371 / journal.pone.0051368 .
  20. ^ RF Hartwick: Distributional ecology and behavior of the early life stages of the box-jellyfish Chironex fleckeri. In: Hydrobiologia. Volume 216/217, 1991, pp. 181-188. (= Proceedings of the Fifth International Conference on Coelenterate Biology. 1989).
  21. ^ RV Southcott: Studies on Australian Cubomedusae, Including a New Genus and Species Apparently Harmful to Man. In: Australian Journal of Marine and Freshwater Research. Volume 7, No. 2, 1956, pp. 254-280.
  22. ^ Flecker, Hugo (1884-1957), by John H. Pearn. Australian Dictionary of Biography, National Center of Biography, Australian National University , accessed November 23, 2016
  23. ^ Collins, Allen G. (2015). Chirodropidae Haeckel, 1880. Accessed via WoRMS World Register of Marine Species , accessed November 23, 2016.
  24. ↑ Bastian Bentlage, Paulyn Cartwright, Angel A. Yanagihara, Cheryl Lewis, Gemma S. Richards, Allen G. Collins: Evolution of box jellyfish (Cnidaria: Cubozoa), a group of highly toxic invertebrates. In: Proceedings of the Royal Society B. Volume 277, No. 1680, 2009, pp. 493-501, doi : 10.1098 / rspb.2009.1707 .

Web links

Commons : Chironex fleckeri  - collection of images