Leafy Seadragon, Phycodurus eques (Günther 1865)


Other Names: Glauert's Sea-dragon, Leafy Sea-dragon
Leafy Seadragon with a parasitic isopod - Rapid Bay, South Australia

Leafy Seadragon, Phycodurus eques, with a parasitic isopod - Rapid Bay, South Australia. Source: Graham Short. License: All rights reserved

Summary:

The spectacular Leafy Seadragon with its elaborate leaf-like appendages and amazing colour pattern is superbly camouflaged amongst kelp and other macroalgae. Eggs laid by the female are brooded by her male partner in a specialised region on the underside of his tail.

The Leafy Seadragon is protected throughout its range in Australia, and is the marine emblem for South Australia.

Spectacular video of Leafy Sea Dragons at Rapid Bay Jetty in South Australia. Filmed and produced by Migration Media.

Beautiful video of a Leafy Sea Dragon

Leafy Seadragons at Rapid Bay Jetty, South Australia

The ARKive project has spectacular images and video footage of Leafy Seadragons feeding and swimming through their habitat, as well as tiny seadragons hatching from eggs carried by the male.

Leafy Seadragons in Gulf St Vincent, off the Yorke Peninsula, South Australia.


Cite this page as:
Bray, D.J. & Thompson, V.J. 2023, Phycodurus eques in Fishes of Australia, accessed 07 Oct 2024, https://fishesofaustralia.net.au/home/species/3126

Leafy Seadragon, Phycodurus eques (Günther 1865)

More Info


Distribution

Endemic to temperate waters of southern Australia, from about Victor Harbor, South Australia, westwards Yanchep Beach, Western Australia, including Kangaroo Island, South Australia. Victorian records have not been verified.

Leafy Seadragons usually inhabit sheltered bays where they are found in seagrass beds especially (Posidonia), and around rocky reefs amongst kelp (Ecklonia) and other macroalgae, at depths of 4-50 metres.

Features

Dorsal fin 34-38; Anal fin 4; Pectoral fin 19-21; Trunk rings 18; Tail rings 41-44; Subdorsal rings 0.50-0.00 + 10.75-12.50 = 11.25-13.00

Body long, slender, contorted, trunk deep in adults; head at right angle to body, snout long. Head and body encased in ring-like bony plates, with elaborate ornamentation of long spines and large leaf-like appendages.

Size

To 35cm total length.

Colour

Leafy Seadragons are greenish to yellowish or brownish-yellow with many thin dark-edged pale lines crossing their sides. They closely resemble kelp or macroalgae.

Feeding

Feed on mysids and other tiny crustaceans. Seahorses, pipefishes and seadragons feed by sucking prey items in through the long, tubular snout.

Biology

The sexes are separate and fertilisation is external. Leafy Seadragons congregate in late winter to form monogamous pairs. Spawning usually occurs during summer, and females deposit their eggs onto a specialised area of spongy tissue on the exposed underside of the male's tail. The eggs become partially embedded in this tissue during embyronic development. After an incubation period of 6-8 weeks, males often migrate to deeper waters (to about 25 m) before the young hatch. The brood hatches over a period of 6-7 days, during which time the male disperses his offspring over a wide area.

Males may care for two broods per season, and incubate 250-300 pear-shaped eggs measuring 4x7mm per brood. Newly hatched young are well developed, very slender and 30-35mm long. They have a small yolk sac, a smaller head and shorter snout than the adults, and the body rings and ridges are indistinct, only becoming visible when the body spines grow. At hatching, the dermal appendages are relatively small, becoming longer and more elaborate with growth.

Juveniles inhabit shallow sheltered waters in association with sand, weed, and rubble in 5-7 m, and are sometimes seen in small aggregations. They feed on tiny mysids and usually grow rapidly during the first few months to almost half the adult size.

Fisheries

Although this charismatic species is eagerly sought by aquarists both in Australia and overseas, Leafy Seadragons are reportedly very difficult to keep in captivity. Wild caught individuals and juveniles born to wild caught males are subsequently reared and sold in Australia and exported overseas for the aquarium trade. The Leafy Seadragon is occasionally taken as bycatch in commercial trawl fisheries.

Conservation

  • EPBC Act 1999 : Listed Marine Species
  • IUCN Red List : Near Threatened 
  • CITES Listed
  • The species is also protected throughout its range by South Australian and Western Australian Government legislation.

    Remarks

    With their colour pattern and frond-like appendages, Leafy Seadragons are remarkably well camouflaged to resemble macroalgae. They also rock back and forth with the wave action looking even more like kelp fronds.

    Similar Species

    The Common Seadragon (Phyllopteryx taeniolatus) is reddish in colour, has simple unbranched appendages, and lacks the long body spines of the Leafy Seadragon. The two species are rarely found together.

    Etymology

    The specific name is from the Latin eques (= horseman, knight, equestrian), which is derived from the Latin equus (= horse) - possibly in reference to the superficial resemblance of the head of this species to that of a horse.

    Species Citation

    Phyllopteryx eques Günther 1865, Proc. Zool. Soc. Lond.: 327, pl. 15. Type locality: Port Lincoln, South Australia.

    Author

    Bray, D.J. & Thompson, V.J. 2023

    Resources

    Atlas of Living Australia

    Leafy Seadragon, Phycodurus eques (Günther 1865)

    References


    Connolly, R.M., Melville, A.J. & Keesing, J.K. 2002. Abundance, movement and identification of individual leafy sea dragons, Phycodurus eques (Pisces: Syngnathidae). Marine and Freshwater Research 53: 777-780.

    Connolly, R.M., Melville, A.J. & Preston, K. 2002. Patterns of movement and habitat use by leafy seadragons tracked ultrasonically. Journal of Fish Biology 61: 684–695.

    Dawson, C.E. 1994. Family Syngnathidae (pp. 441-474). In Gomon M.F., C.J.M. Glover & R.H. Kuiter (eds.) The fishes of Australia's south coast. State Print, Adelaide, 992 pp.

    Edgar, G.J. 2008. Australian Marine Life: the plants and animals of temperate waters. Sydney : Reed New Holland 2nd edn, 624 pp.

    Gomon, M.F. & Neira, F.J. 1998. Syngnathidae: pipefishes and seahorses. pp. 122-131 in Neira, F.J., Miskiewicz, A.G. & Trnski, T. Larvae of temperate Australian fishes: laboratory guide for larval fish identification. Nedlands, Western Australia : University of Western Australia press 474 pp.

    Günther, A. 1865. On the pipe-fishes belonging to the genus Phyllopteryx. Proceedings of the Zoological Society London 1865: 327-328, pls. 15-16. See ref at BHL

    Hoschke, A., Whisson, G. & Moore, G.I. 2019. Complete list of fishes from Rottnest Island. pp. 150-161 in Whisson, G. & Hoschke, A. (eds) The Rottnest Island fish book. 2nd ed. Perth, Western Australia : Aqua Research and Monitoring Services.

    Hutchins, J.B. 1994. A survey of the nearshore reef fish fauna of Western Australia's west and south coasts — The Leeuwin Province. Records of the Western Australian Museum, Supplement 46: 1-66 figs 1-6 

    Hutchins, J.B. 2005. Checklist of marine fishes of Recherche Archipelago and adjacent mainland waters. pp. 425-449 in Wells, F.E., Walker, D.I. & Kendrick, G.A. (eds). Proceedings of the Twelfth International Marine Biological Workshop: The Marine Flora and Fauna of Esperance, Western Australia. Perth : Western Australian Museum. 

    Hutchins, J.B. & Thompson, M. 1983. The Marine and Estuarine Fishes of South-western Australia. Perth : Western Australian Museum 103 pp. 345 figs.

    Kuiter, R.H. 1988. Birth of a Leafy Sea-dragon. Journal of the Australian Geographic Society 12: 91-97.

    Kuiter, R.H. 1993. Coastal Fishes of South-eastern Australia. Bathurst : Crawford House Press 437 pp. 

    Kuiter, R.H. 1996. Guide to Sea Fishes of Australia. A comprehensive reference for divers and fishermen. Sydney, NSW, Australia : New Holland Publishers xvii, 434 pp.

    Kuiter, R.H. 2000. Seahorses, Pipefishes and Their Relatives. Chorleywood, UK : TMC Publishing 240 pp.

    Kuiter, R.H. 2008. Syngnathidae. pp. 448-479 in Gomon, M.F., Bray, D.J. & Kuiter, R.H. (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp. 

    Kuiter, R.H. 2009. Seahorses and their relatives. Seaford, Australia : Aquatic Photographics, 331 pp.

    Larson, S., Ramsey, C., Tinnemore, D. & Amemiya, C. 2014. Novel microsatellite loci variation and population genetics within leafy seadragons, Phycodurus eques. Diversity 6(1): 33-42. https://doi.org/10.3390/d6010033

    Martin-Smith, K.M. & Vincent, A.C.J. 2006. Exploitation and trade of Australian seahorses, pipehorses, sea dragons and pipefishes (Family Syngnathidae). Oryx 40(2): 141-151.

    Pollom, R. 2017. Phycodurus eques. The IUCN Red List of Threatened Species 2017: e.T17096A67622420. https://dx.doi.org/10.2305/IUCN.UK.2017-2.RLTS.T17096A67622420.en. Accessed on 10 August 2023.

    Stiller, J., Wilson, N.G., Donnellan, S. & Rouse, G.W. 2017. The Leafy Seadragon, Phycodurus eques, a flagship species with low but structured genetic variability. Journal of Heredity 108(2): 152–162, https://doi.org/10.1093/jhered/esw075

    Stiller, J., Wilson, N.G. & Rouse, G.W. 2015. A spectacular new species of seadragon (Syngnathidae). Royal Society open science 2: 1-12 https://doi.org/10.1098/rsos.140458

    Whitley, G.P. 1939. Studies in Ichthyology No. 12. Records of the Australian Museum 20(4): 264-277 figs 1-3 https://doi.org/10.3853/j.0067-1975.20.1939.576 (described as Phycodurus glauerti, type locality Rottnest Island, WA) 

    Wilson, N.G. & Rouse, G.W. 2010. Convergent camouflage and the non-monophyly of ‘seadragons’ (Syngnathidae: Teleostei): suggestions for a revised taxonomy of syngnathids. Zoologica Scripta 39: 551–558.

    Quick Facts


    CAAB Code:37282001

    Biology:Males brood the eggs

    Conservation:IUCN Least Concern

    Depth:4-50 m

    Habitat:Reef associated, macroalgae/seagrass

    Max Size:35 cm TL

    Native:Endemic

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