Common seadragon | |
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Phyllopteryx taeniolatus in Cabbage Tree Bay, Sydney, Australia | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Syngnathiformes |
Family: | Syngnathidae |
Genus: | Phyllopteryx |
Species: | P. taeniolatus |
Binomial name | |
Phyllopteryx taeniolatus (Lacepède, 1804) | |
Phyllopteryx taeniolatus range | |
Synonyms [2] | |
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The common seadragon or weedy seadragon (Phyllopteryx taeniolatus) is a marine fish of the order Syngnathiformes, which also includes the similar pipefishes, seahorses, and trumpetfishes among other species. Adult common seadragons are a reddish colour, with yellow and purple striped markings; they have small, leaf-like appendages that resemble kelp or seaweed fronds, providing camouflage, as well as a number of short spines for protection. [3] [4] As with seahorses and the other syngnathids, the seadragon has a similarly tubular snout and a fused, toothless jaw into which it captures small invertebrate prey at lightning speed. Males have narrower bodies and are darker than females. [4] Seadragons have a long dorsal fin along the back and small pectoral fins on either side of the neck, which provide balance. [5] Weedy seadragons can reach 45 cm (18 in) in length.
The seadragon is the marine emblem of the Australian state of Victoria. [6]
The common seadragon is endemic to Australian and insular coastal waters of the eastern Indian Ocean northern Southern Ocean and the southwestern Pacific Ocean. It can generally be found along the entire southern coastline of the Australian continent, including Tasmania and other offshore islands. It can be observed regularly from around Port Stephens, New South Wales to Geraldton, Western Australia, as well as off the coast of South Australia and the Great Australian Bight. [2]
The common seadragon inhabits coastal waters down around 10 m (33 ft) to 30 m (98 ft) deep. It is associated with rocky reefs, seaweed beds, seagrass meadows and structures colonised by seaweed. [7]
The seadragons are slow-moving and, like most of their relatives, rely on excellent camouflage—the mimicry of seaweed, in this case—as a defense against predators. They lack the prehensile tail that many seahorses and pipefishes have evolved as anchors, to clasp and steady themselves; seadragons, instead, drift in the water among kelp and seaweed masses, which they blend-into with their leafy-looking appendages. [4]
Individuals are observed either on their own or in pairs, feeding on tiny crustaceans and other zooplankton by sucking prey into their toothless mouths. As with most other syngnathids, seadragon males are the sex that cares for the developing eggs. Females lay around 120 eggs onto the brood patch located on the underside of the male's tail. The eggs are fertilised and carried by the male for around a month before the hatchlings emerge. [4] The young are independent at birth, beginning to eat shortly after. [8] Common seadragons take about 28 months to reach sexual maturity, and may live for up to six years. [9]
Mating in captivity is relatively rare since researchers have yet to understand what biological or environmental factors trigger them to reproduce. The survival rate for young common seadragons is low in the wild, but it is about 60% in captivity. [10]
The Aquarium of the Pacific (in Long Beach, California) and the Tennessee Aquarium (in Chattanooga, Tennessee), [11] in the US, and Melbourne Aquarium in Melbourne, Australia [12] are among the few facilities in the world to have successfully bred common seadragons in captivity, though others occasionally report egg-laying. In March 2012, Georgia Aquarium (in Atlanta) announced a successful breeding event of common seadragons. [13] In July of the same year, Monterey Bay Aquarium, on California's central coast, successfully bred and hatched-out common seadragons, on-exhibit. [14] Most recently, Birch Aquarium (in La Jolla, San Diego, California) successfully bred and hatched common seadragon fry in early 2023. [15]
Aquarium keepers must make adjustments to the water, food, tank setup, and captivity procedures, as many studies have shown that sea dragons are prone to diseases and infections such as scuticociliatosis, myxozoanosis, fungal infections, intestinal coccidiosis, neoplasia, and swim bladder issues, which can result from parasites growing in their bodies due to their captive environment (Bonar, C. J., Garner, M. M., Weber, E. S., et al. 2013). [16]
The common seadragon is classified as Least Concern (LC) on the IUCN Red List. [1] While the common seadragon is a desired species in the international aquarium trade, the volume of wild-caught individuals is small and therefore not currently a major threat. Instead, habitat loss and degradation due to human activities and pollution threaten common seadragons most. [1]
The loss of suitable seagrass beds and loss of canopy seaweed from inshore rock reefs, coupled with natural history traits that make them poor dispersers, put the future of seadragon populations at risk. This species is not at present a victim of bycatch or a target of trade in traditional Chinese medicine, two activities which are currently a threat to many related seahorse and pipefish populations. [17] [18]
More recent research suggests that the weedy seadragon may be far more endangered than initially assumed as a result of climate change-induced marine heatwaves on the Great Southern Reef. Edgar et al (2023) documented a population decline of 59% between 2011 and 2021, a period of frequent and extensive marine heatwaves. This would be enough to classify it as Endangered on the IUCN Red List. [19]
It is illegal to take or export these species in most of the states within which they occur. [4] A database of seadragon sightings, known as 'Dragon Search' has been established with support from the Marine Life Society of South Australia Inc., ('Dragon Search' arose as the logical progression of a similar project initiated by the MLSSA, which was the first community group or indeed organisation of any type to adopt the common seadragon's close relative, the leafy seadragon, as part of its logo), the Marine and Coastal Community Network (MCCN), the Threatened Species Network (TSN) and the Australian Marine Conservation Society (AMCS), which encourages divers to report sightings. [4] Monitoring of populations may provide indications of local water quality and seadragons could also become an important 'flagship' species for the often-overlooked richness of the unique flora and fauna of Australia's south coast. [4]
Captive breeding programs are in place for the weedy seadragon, headed up by Sea Life Melbourne Aquarium. [20] [21] The dragon has been difficult to breed in captivity, though in 2015, research observing the creatures in the wild and trying to replicate the conditions in captivity had researchers making changes to the light, water temperature and water flow proving to be key. [22]
In December 2015, the Melbourne aquarium hatched eggs and the aquarium's weedy seadragon population significantly increased. The aquarium reported in March 2016 that 45 fry were still going strong, a 95% survival rate. [23]
The common seadragon is in the subfamily Syngnathinae, which contains all pipefish. It is most closely related to the other member of its genus, the ruby seadragon (Phyllopteryx dewysea), and also the leafy seadragon (Phycodurus eques). Haliichthys taeniophorus , sometimes referred to as the "ribboned seadragon" is not closely related (it does not form a true monophyletic clade with weedy and leafy seadragons). [24]
The common seadragon was previously the only member of its genus until the description of the ruby seadragon in 2015. [25]
In the November 2006 issue of National Geographic magazine, marine biologist Greg Rouse is reported as investigating the DNA variation of the two seadragon species across their ranges.
A seahorse is any of 46 species of small marine bony fish in the genus Hippocampus. "Hippocampus" comes from the Ancient Greek hippókampos (ἱππόκαμπος), itself from híppos (ἵππος) meaning "horse" and kámpos (κάμπος) meaning "sea monster" or "sea animal". Having a head and neck suggestive of a horse, seahorses also feature segmented bony armour, an upright posture and a curled prehensile tail. Along with the pipefishes and seadragons they form the family Syngnathidae.
Shedd Aquarium is an indoor public aquarium in Chicago. Opened on May 30, 1930, the 5 million US gal aquarium holds about 32,000 animals and is the third largest aquarium in the Western Hemisphere, after the Georgia Aquarium and Monterey Bay Aquarium.
The leafy seadragon or Glauert's seadragon, is a marine fish. It is the only member of the genus Phycodurus in the family Syngnathidae, which includes seadragons, pipefish, and seahorses.
Sea Dragon or seadragon may refer to:
The Syngnathidae is a family of fish which includes seahorses, pipefishes, and seadragons. The name is derived from Ancient Greek: σύν, meaning "together", and γνάθος, meaning "jaw". The fused jaw is one of the traits that the entire family have in common.
Pipefishes or pipe-fishes (Syngnathinae) are a subfamily of small fishes, which, together with the seahorses and seadragons, form the family Syngnathidae.
Sea Life Melbourne Aquarium is a Southern Ocean and Antarctic aquarium in central Melbourne, Australia. It is located on the banks of the Yarra River beside and under the Flinders Street Viaduct and the King Street Bridge. The attraction is a Sea Life Centre owned by Merlin Entertainments.
Paracanthurus hepatus is a species of Indo-Pacific surgeonfish. A popular fish in marine aquaria, it is the only member of the genus Paracanthurus. A number of common names are attributed to the species, including regal tang, palette surgeonfish, blue tang, royal blue tang, hippo tang, blue hippo tang, flagtail surgeonfish, Pacific regal blue tang, and blue surgeonfish.
The Syngnathiformes are an order of ray-finned fishes that includes the leafy seadragons, sea moths, trumpetfishes and seahorses, among others.
Birch Aquarium is a public aquarium in La Jolla, a community of San Diego, California. It serves as the public outreach center for Scripps Institution of Oceanography at the University of California, San Diego, with over half a million people visiting the aquarium each year.
The Shanghai Ocean Aquarium is a public aquarium located in Shanghai, China.
The Hippocampinae are a subfamily of small marine fishes in the family Syngnathidae. Depending on the classification system used, it comprises either seahorses and pygmy pipehorses, or only seahorses.
Amanda Vincent is a Canadian marine biologist and conservationist, one of the world's leading experts on seahorses and their relatives. She currently holds the chair of the IUCN SSC Seahorse, Pipefish and Seadragon Specialist Group and is the marine representative on the IUCN's International Red List Committee as well as being the chair of its Marine Conservation Committee. She previously held the Canada Research Chair in Marine Conservation at the UBC Institute for the Oceans and Fisheries at the University of British Columbia (UBC), Canada from 2002 to 2012. Vincent co-founded and directs Project Seahorse, an interdisciplinary and international organization committed to conservation and sustainable use of the world's coastal marine ecosystems. In 2020 she became the first marine conservationist to win the world's leading prize for animal conservation, the Indianapolis Prize.
Pregnancy has been traditionally defined as the period of time eggs are incubated in the body after the egg-sperm union. Although the term often refers to placental mammals, it has also been used in the titles of many international, peer-reviewed, scientific articles on fish, e.g. Consistent with this definition, there are several modes of reproduction in fish, providing different amounts of parental care. In ovoviviparity, there is internal fertilization and the young are born live but there is no placental connection or significant trophic (feeding) interaction; the mother's body maintains gas exchange but the unborn young are nourished by egg yolk. There are two types of viviparity in fish. In histotrophic viviparity, the zygotes develop in the female's oviducts, but she provides no direct nutrition; the embryos survive by eating her eggs or their unborn siblings. In hemotrophic viviparity, the zygotes are retained within the female and are provided with nutrients by her, often through some form of placenta.
The ruby seadragon is a marine fish in the family Syngnathidae, which also includes seahorses. It inhabits the coast of Western Australia. The species was first described in 2015, making it only the third known species of seadragon, and the first to be discovered in 150 years. A specimen found on shore in 2007 was 23.5 cm (9.3 in) long.
Phyllopteryx is a genus of small fishes, commonly called seadragons, in the family Syngnathidae that are found along the western and southern coasts of Australia. Since the 19th century, the weedy or common seadragon was the only known species, until the description of the ruby seadragon in 2015. They are closely related to other members of the Syngnathidae such as the leafy seadragon, pipefish and seahorses, which all exhibit male pregnancy.
The Great Southern Reef is a system of interconnected reefs that spans the southern coast of continental Australia and Tasmania and extends as far north as Brisbane to the east and Kalbarri to the west. It covers 71,000 km2 (27,000 sq mi) of ocean and straddles five states, running along the coast for 8,000 km (5,000 mi).
Acentronura breviperula, also known as the shortpouch pygmy pipehorse, dwarf pipehorse and northern little pipehorse, is a species of pygmy pipehorse, a member of the family Syngnathidae, the seahorses and pipefishes. It occurs in the Indo-Pacific region from the eastern Andaman Sea, through the Malay Archipelago to the Western Pacific as far east as New Guinea and the northern Great Barrier Reef.
Nannocampus pictus, also known as the reef pipefish, is a species of marine fish belonging to the family Syngnathidae. They can be found inhabiting reefs and seagrass beds of the western Indian Ocean and the eastern coast of Australia including the Great Barrier Reef. Members of this species can grow to lengths of 10 cm and their diet likely consists of small crustaceans such as copepods. Reproduction occurs through ovoviviparity in which the males brood eggs before giving live birth.
Leafy seadragons are widely recognized for their strikingly derived characters, including leaf-like appendages, extreme spinal curvature, elongated craniofacial bones, and large body size. These make them phenotypic outliers in the teleost fish clade . Up until recently, the genome of leafy seadragons was unknown; but in 2022, their genome was fully annotated, along with weedy seadragons. Several significant features have been found in the leafy seadragon and weedy seadragon genomes, including divergent noncoding regions near a developmental gene responsible for integumentary growth; high genome wide repetitive DNA density; and recent transposable element expansions. Genetic diversity in leafy seadragons and weedy seadragons is relatively low as they have low-dispersal life history. Most recently, another species of seadragon was discovered and genetically sequenced: the ruby seadragon, which differs genetically and phenotypically from the two other seadragon species.
This article incorporates text from the ARKive fact-file "Common seadragon" under the Creative Commons Attribution-ShareAlike 3.0 Unported License and the GFDL .