Weird fish of the week: Weedy sea dragon


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The Weedy sea dragon is a member of the Syngnathidae family, a group of that contains the seahorses and pipefish. We're all so familiar with seahorses that their weirdness has become almost unremarkable but this really is something wonderfully peculiar!

Let's face it, the seahorses are not really that similar to their equine namesakes are they? There's the distinct absence of hooves for a start, which isn't surprising given the lack of legs to put them on and I've yet to see a horse with a prehensile tail. Their common name's nod to nags is purely because of the shape of their heads, unless they have a love of sugar lumps I'm unaware of.

By contrast the Weedy sea dragon (Phyllopteryx taeniolatus) really does live up to its mythological moniker perhaps with the exception of fire breathing...

Check out the amazing video below:

Growing to around 45cm/18in, these marvellous mimics really do look like small dragons, complete with a set of wing like fins on their backs. Add to this their armoured body covered in bony plates, long tail and crested head and the sea dragon name really fits.

Their odd body shape is explained by their natural habitat. They are found along the temperate coast of South Australia in amongst kelp and other sea weeds and in these swaying algae forests they are especially cryptic as they hunt for their typical prey of mysids and other tiny marine crustaceans.

They lack a caudal fin and are poor swimmers, moving by the energetic fanning of their dorsal and pectorals. The fish pair up to breed in early summer, performing elaborate, synchronised swimming displays after which the female lays up to 250 eggs which are attached to the tail of the male.

The female plays no further part in the care of the eggs which the male now carries embedded in his tail for the next couple of months until they hatch into fully formed miniature versions of their parents.

There are unfortunately a number of threats to these fantastical fish, largely due to habitat damage. Commercial fishing of rock lobster has led to an increase in the population of the sea urchin species Centrostephanus rogersii on which the lobster preys. This urchin eats the seaweed and kelp that gives the sea dragons and their food shelter leaving them open to predation and starvation as well as an increased risk of being swept ashore during stormy weather.

Habitat degradation caused by human activity such as dredging, land reclamation, drainage run-off etc has also impacted on their distribution. These and other factors have led to Phyllopteryx taeniolatus being listed as 'Near threatened' on the IUCN red list.

Why not check out some of our other Weird fish of the week features? Barreleye 

Mega mouth shark

Flying gurnard

Pinecone fish

Sea lamprey

Slender snipe eel

Tripod fish


Ocean sunfish

Two-headed arowana


Giant oarfish

Kroyer's deep sea anglerfish

Halimeda ghost pipefish