Chiropsella bronzie

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Chiropsella bronzie
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Cnidaria
Class: Cubozoa
Order: Chirodropida
Family: Chiropsellidae
Genus: Chiropsella
Species:
C. bronzie
Binomial name
Chiropsella bronzie
Gershwin, 2006

Chiropsella bronzie is a species of box jellyfish. [1] It is considered much less of a threat to humans than some of its relatives. The species was described in 2006, and is one of four species in the genus Chiropsella. [2] Chiropsella bronzie can be found in shallow waters off the coast of Queensland, Australia. [2]

Contents

Taxonomy

Chiropsella bronzie was previously misidentified in 1880 as Chiropsalmus quadrigata , an Indian Ocean cubozoan of the same order. [3] It was later correctly identified as a new species by Gershwin in 2006. [2] The species name bronzie is named after the Royal Life Saving Society's bronze medallion award for a qualified Life Saver. [2]

The order Chirodropida consists of three major families: Chirodropidae, Chiropsalmidae , and Chiropsellidae containing the genera Meteorona and Chiropsella. Out of all cubozoan relationships, research has shown that the Meteorona kishinouyei and Chiropsella bronzie are the closest relatives, as they are the most phylogenically similar. [4] Both species have similar morphological traits, such as an unbranched gastrovascular cavity saccule, whereas most other cubozoans' gastro cavity saccules are branched. [4] Some morphological traits used to distinguish the two species are differences in number of tentacles and pedalium shape.

A morphological exception that C. bronzie holds, compared to other members of the order Chirodropida, is the presence of gastric filaments in its stomach, where other members lack these structures. [4] Because of this exception, there has been proposals of adjusting Chirodropida taxonomy with the potential addition of another family.

Description

Chiropsella bronzie belongs to the order Chirodropida, which can be distinguished from other box jellyfish by the presence of muscular masses on the medusa's four corners and saccules found in the gastrovascular cavity. The adult bell of the Chiropsella bronzie is small and rounded, and ranges from 3 to 5 cm in diameter, [5] not exceeding 8 cm high and wide. [2] Each corner of the C. bronzie medusae holds up to 9 tentacles on each stalk, or pedalium. [6] [2]

Chiropsella bronzie and other box jellyfish have very developed eyes and sensory structures. Box jellyfish have true eyes, which are found in clusters called rhopalia. Chiropsella bronzie has 24 eyes and 4 morphologically different types on rhopalia, Two of these eyes are camera type eyes, which consist of one upper lens and one lower lens eyes, and two pigment slit eyes. However, similar to Tripedalia cystophora , C. bronzie have shown to have weaker eyes than other cubazoa species due to weaker lenses to focus images on the retina. [7] This is most likely due to eyes being ellipsoid in shape and very soft, unlike the spherical shape of other cubozoa that contain more sensory power. [7] Research also suggests that C. bronzie are most likely color blind, a factor that does not inhibit obstacle avoidance. [8] [5] This variation in box jellyfish sensory systems is expected due to the wide range of habitat cubozoa occupy, including sandy beaches, mangroves, kelp forests, the open ocean, and coal reefs. [8] [9] The complexity of box jellyfish eyes allows for more advanced swimming and navigational behavior, such as increased awareness of surroundings and directional swimming.

Distribution and habitat

Cubozoan are distributed globally, but are commonly found in tropical waters in the Indo-Pacific region. C. bronzie is located in shallow waters near Queensland, Australia, [10] specifically from Cooktown to Townsville, Australia. [6] These beach habitats contain mangrove trees, sandy bottoms, and coral reefs. After heavy rainfalls, C. bronzie habitats include sunken natural debris, such as branches and large rocks, that jellyfish need to navigate. [5]

Ecology

The life cycle of cubozoans can be simplified down to four stages: egg, swimming larvae, sessile polyps, and swimming medusae. Body plans are reorganized between each stage during metamorphosis, with the exception of development from egg to larvae. In the final metamorphosis, box jellyfish develop complex nervous systems, including advanced visual organs. [11] The rhopalia nervous system (RNS) is also developed during the final body reorganization. [11]

Box jellyfish can exhibit both asexual and sexual reproduction. Sexual reproduction occurs during the medusa stage, where the adult male jellyfish releases sperm into the water, and the female releases eggs to be fertilized. In some cases, the male medusa can directly inseminate the female using a sperm packet. In this case, the eggs will develop inside the bell as opposed to the open water. [12] Fertilized eggs then develop into a jellyfish larvae stage called a planula. These larvae contain cilia that allow them to swim throughout the water column. Box jellyfish remain in the planula larvae phase until settling on a hard surface on the seafloor where they will develop into a polyp.

Box jellyfish can also reproduce by means of asexual reproduction through budding, where settled jellyfish polyps can create small cloned "buds" on their body stalks. Once a bud is fully formed, it will break off of the polyp and develop into a medusae. Another difference between true jellyfish (scyphozoans) and cubozoans is that the entire cubozoan polyp develops into a medusae, as opposed to going through strobilation. [13] The habitat of Chiropsella bronzie polyps is still unknown, but research suggests they settle near or on beaches and mangroves. [10] In addition, it is unknown how long C. bronzie remains in the polyp stage before maturing to their final medusa stage. Once reaching the final stage, adult box jellyfish will spawn and begin the reproductive cycle again. Cubozoans have shown to have short life spans of two years of less.

Behavior

Box jellyfish tend to move much faster than other jellyfish, with Chiropsella bronzie having a maximum speed of 7–8 cm per second against a 1 cm per second current. [5] Unlike true jellyfish who tend to simply float along with currents, cubozoans are known to be effective predators that hunt using their complex eyes. Their prey consists of mostly shrimp, specifically Acestes australis. [5]

Sting and toxicity

The venom contained in C. bronzie’s cnidocytes is much less potent than other cubozoans, as there has been no evidence that C. bronzie can deliver a lethal sting to a human. [2] However, studies have shown that the venom of C. bronzie has adversely affected the cardiovascular system of anesthetized rats in laboratory settings by greatly lowering their heart rate. [14] The venom of C. bronzie may be very similar to that of Chironex fleckeri , but potentially less potent. This could be confirmed by the fact C. bronzie are more abundant than C. fleckeri, but have no history to be the cause of human fatalities. [10] A stronger venom would also allow C. bronzie to feed on fish, while their diet is limited to smaller prey, like shrimp. More research is needed to increase understanding of just how harmful the venom of C. broznie can be to humans.

Related Research Articles

<span class="mw-page-title-main">Cnidaria</span> Aquatic animal phylum having cnydocytes

Cnidaria is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine environments, predominantly the latter.

<span class="mw-page-title-main">Jellyfish</span> Soft-bodied, aquatic invertebrates

Jellyfish and sea jellies are the informal common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals with umbrella-shaped bells and trailing tentacles, although a few are anchored to the seabed by stalks rather than being mobile. The bell can pulsate to provide propulsion for highly efficient locomotion. The tentacles are armed with stinging cells and may be used to capture prey and defend against predators. Jellyfish have a complex life cycle; the medusa is normally the sexual phase, which produces planula larvae that disperse widely and enter a sedentary polyp phase before reaching sexual maturity.

<span class="mw-page-title-main">Scyphozoa</span> Class of marine cnidarians, true jellyfish

The Scyphozoa are an exclusively marine class of the phylum Cnidaria, referred to as the true jellyfish.

<span class="mw-page-title-main">Box jellyfish</span> Class of cnidarians distinguished by their cube-shaped medusae

Box jellyfish are cnidarian invertebrates distinguished by their box-like body. Some species of box jellyfish produce potent venom delivered by contact with their tentacles. Stings from some species, including Chironex fleckeri, Carukia barnesi, Malo kingi, and a few others, are extremely painful and often fatal to humans.

<span class="mw-page-title-main">Rhopalium</span>

Rhopalia are small sensory structures of certain Scyphozoan and Cubozoan species.

<i>Chironex fleckeri</i> Species of jellyfish

Chironex fleckeri, commonly known as the Australian box jelly, and nicknamed the sea wasp, is a species of extremely venomous box jellyfish found in coastal waters from northern Australia and New Guinea to Malaysia, the Philippines and Vietnam. It has been described as "the most lethal jellyfish in the world", with at least 64 known deaths in Australia from 1884 to 2021.

<span class="mw-page-title-main">Medusozoa</span> Clade of marine invertebrates

Medusozoa is a clade in the phylum Cnidaria, and is often considered a subphylum. It includes the classes Hydrozoa, Scyphozoa, Staurozoa and Cubozoa, and possibly the parasitic Polypodiozoa. Medusozoans are distinguished by having a medusa stage in their often complex life cycle, a medusa typically being an umbrella-shaped body with stinging tentacles around the edge. With the exception of some Hydrozoa, all are called jellyfish in their free-swimming medusa phase.

<i>Carybdea</i> Genus of jellyfishes

Carybdea is a genus of venomous box jellyfish within the family Carybdeidae that currently consists of a total of 8 species. This genus of jellyfish are often found in warm waters around the world in waters such as the Mediterranean Sea, the Pacific Ocean, and off the coast of Africa. Their sting can cause a range of effects depending on the species. These invertebrates will go through both sexual and asexual reproduction as they transform from a polyp to medusa. Carybdea have a box-shaped bell with four tentacles and eye-like sensory structures. There are distinct physical markings that differentiate many species within the genus. While Carybdea use their venom to act as predators, they are also preyed on by turtles and various fish. They feed on plankton, invertebrates, fish, and some crustaceans.

<span class="mw-page-title-main">Chirodropidae</span> Family of jellyfishes

Chirodropidae is a family of venomous box jellyfish within the class Cubozoa. Like other members of the order Chirodropida, they have branched pedalia, in contrast to the unbranched pedalia of box jellyfish in the order Carybdeida. Each branch houses its own individual tentacle. Nematocyst composition and type can vary among individuals within this family based on body size and life stage. Like other box jellyfish, chirodropids can be found in coastal and shallow marine areas, but they have also been found to occur at benthic depths.

<i>Turritopsis dohrnii</i> Species of small, biologically immortal jellyfish

Turritopsis dohrnii, also known as the immortal jellyfish, is a species of small, biologically immortal jellyfish found worldwide in temperate to tropic waters. It is one of the few known cases of animals capable of reverting completely to a sexually immature, colonial stage after having reached sexual maturity as a solitary individual. Others include the jellyfish Laodicea undulata and species of the genus Aurelia.

<i>Carukia barnesi</i> Species of jellyfish

Carukia barnesi is an extremely venomous jellyfish found near Australia. Stings can result in Irukandji syndrome, and this species is commonly known as Irukandji jellyfish, although this name does not distinguish it from other Irukandji jellyfish such as Malo kingi.

<i>Aurelia</i> (cnidarian) Genus of jellyfish

Aurelia is a genus of scyphozoan jellyfish, commonly called moon jellies. There are currently 25 accepted species and many that are still not formally described.

<i>Turritopsis nutricula</i> Species of hydrozoan

Turritopsis nutricula is a small hydrozoan that once reaching adulthood, can transfer its cells back to childhood. This adaptive trait likely evolved in order to extend the life of the individual. Several different species of the genus Turritopsis were formerly classified as T. nutricula, including the "immortal jellyfish" which is now classified as T. dohrnii.

<i>Copula sivickisi</i> Species of jellyfish

Copula is a monotypic genus of box jellyfish in the family Tripedaliidae of the phylum Cnidaria. The only species in the genus is Copula sivickisi, a very small gelatinous, bell-shaped jellyfish with four tentacles that is active only at night. It is unusual among box jellyfish in having a mating ritual and internal fertilization. Its scientific name honours the Lithuanian zoologist Pranciškus Baltrus Šivickis.

<i>Tripedalia cystophora</i> Species of jellyfish

Tripedalia cystophora is a small species of box jellyfish in the family Tripedaliidae. It is native to the Caribbean Sea and the Central Indo-Pacific.

<i>Carybdea marsupialis</i> Species of jellyfish

Carybdea marsupialis, is a venomous species of box jellyfish, in the small family Carybdeidae within the class Cubozoa.

<i>Chironex yamaguchii</i> Species of jellyfish

Chironex yamaguchii, commonly known as ハブクラゲ and as "hub jellyfish" due to erroneous machine translations, is a species of box jellyfish found in coastal waters around Japan, on Okinawa and the Ryukyu Islands, and in the Philippines. Discovered in 2009, it is highly venomous and has been the cause of several deaths in Japanese waters.

<i>Chiropsoides</i> Genus of jellyfishes

Chiropsoides is a genus of box jellyfish in the family Chiropsalmidae. It is monotypic, with a single species, Chiropsoides buitendijki. The most distinct species characteristics are the shape of the gastric saccules, the pedalial canals, and the unilateral pedalial branching.

<i>Chironex indrasaksajiae</i> Species of jellyfish

Chironex indrasaksajiae, locally known as Mangkaprun Klong, Mangkaprun Sarhai or Sarong, is a species of box jellyfish in a coastal water of the northern and eastern Gulf of Thailand. It has been accused of causing fatalities in the area as it is a member of the genus Chironex.

<i>Tamoya haplonema</i> Species of box jellyfish

Tamoya haplonema is a species of box jellyfish in the genus Tamoya. It is the type species of the genus and was described in 1859. The medusa possesses four tentacles, one each on an inter-radial pedal.

References

  1. Collins, A.G.; Jarms, G. (2021). "World List of Cubozoa. Chiropsella bronzie Gershwin, 2006". WoRMS. World Register of Marine Species . Retrieved 5 April 2021.
  2. 1 2 3 4 5 6 7 Gershwin, Lisa-ann (2006-06-12). "Comments on Chiropsalmus (Cnidaria: Cubozoa: Chirodropida): a preliminary revision of the Chiropsalmidae, with descriptions of two new genera and two new species". Zootaxa. 1231 (1): 1. doi:10.11646/zootaxa.1231.1.1. ISSN   1175-5334.
  3. "WoRMS - World Register of Marine Species - Chiropsalmus quadrigatus Haeckel, 1880". www.marinespecies.org. Retrieved 2021-04-01.
  4. 1 2 3 Toshino, Sho; Miyake, Hiroshi; Shibata, Haruka (2015-05-11). "Meteorona kishinouyei, a new family, genus and species (Cnidaria, Cubozoa, Chirodropida) from Japanese Waters". ZooKeys (503): 1–21. doi: 10.3897/zookeys.503.9047 . ISSN   1313-2989. PMC   4440269 . PMID   26019668.
  5. 1 2 3 4 5 Garm, A.; O'Connor, M.; Parkefelt, L.; Nilsson, D.-E. (2007-10-15). "Visually guided obstacle avoidance in the box jellyfish Tripedalia cystophora and Chiropsella bronzie". Journal of Experimental Biology. 210 (20): 3616–3623. doi: 10.1242/jeb.004044 . ISSN   0022-0949. PMID   17921163.
  6. 1 2 Bentlage, Bastian (2013). "Description of the chirodropid box jellyfish Chiropsella rudloei sp. nov. (Cnidaria: Cubozoa) from Madagascar". Marine Biodiversity Records. 6: e118. doi:10.1017/S1755267213000924. ISSN   1755-2672.
  7. 1 2 O’Connor, Megan; Garm, Anders; Nilsson, Dan-E. (2009-06-01). "Structure and optics of the eyes of the box jellyfish Chiropsella bronzie". Journal of Comparative Physiology A. 195 (6): 557–569. doi:10.1007/s00359-009-0431-x. ISSN   1432-1351. PMID   19347342. S2CID   9563849.
  8. 1 2 Coates, M. M. (2003-08-01). "Visual Ecology and Functional Morphology of Cubozoa (Cnidaria)". Integrative and Comparative Biology. 43 (4): 542–548. doi: 10.1093/icb/43.4.542 . ISSN   1540-7063. PMID   21680462.
  9. Morandini, André Carrara; Soares, Marcelo de Oliveira; Matthews-Cascon, Helena; Marques, Antonio Carlos (2006). "A survey of the Scyphozoa and Cubozoa (Cnidaria, Medusozoa) from the Ceará coast (NE Brazil)". Biota Neotropica. 6 (2). doi: 10.1590/s1676-06032006000200021 . ISSN   1676-0603.
  10. 1 2 3 Gordon, M.; Hatcher, C.; Seymour, J. (November 2004). "Growth and age determination of the tropical Australian cubozoan Chiropsalmus sp". Hydrobiologia. 530–531 (1–3): 339–345. doi:10.1007/s10750-004-2655-7. ISSN   0018-8158. S2CID   24935723.
  11. 1 2 Gurska, Daniela; Garm, Anders (2014-07-21). "Cell Proliferation in Cubozoan Jellyfish Tripedalia cystophora and Alatina moseri". PLOS ONE. 9 (7): e102628. Bibcode:2014PLoSO...9j2628G. doi: 10.1371/journal.pone.0102628 . ISSN   1932-6203. PMC   4105575 . PMID   25047715.
  12. "Stinging cells help jellyfish to mate". Nature. 524 (7566): 390. August 2015. doi: 10.1038/524390c . ISSN   1476-4687.
  13. says, Hatty Shi (2017-03-13). "How Do Box Jellyfish Reproduce | Box Jellyfish Life Cycle & Reproduction -". Box Jellyfish. Retrieved 2021-04-01.
  14. Winter, Kelly L.; Fernando, Ross; Ramasamy, Sharmaine; Seymour, Jamie E.; Isbister, Geoffrey K.; Hodgson, Wayne C. (2007-01-10). "The in vitro vascular effects of two chirodropid (Chironex fleckeri and Chiropsella bronzie) venoms". Toxicology Letters. 168 (1): 13–20. doi:10.1016/j.toxlet.2006.10.011. ISSN   0378-4274. PMID   17141433.