Dragonet of some sort?

This is a Slender Seamoth Pegasus volitans.  I'm guessing probably caught in the Swan, or perhaps Cockburn Sound?  These are frequently caught while dragging for prawns.

yep from the swan, and not from dragging either :)

Also known as Longtail Seamoth, Slender Seamoth are light brown or olive to dark brown with a paler belly.  They have a flattened head and tapered body covered by a bony skeleton of rigid plates.  The tail is enclosed in bony rings.  The white tipped snout is long and made up of modified nose bones and there is a small mouth under the snout.  They have large pectoral fins which are spread out like wings.  Slender Seamoths are adapted to walk over the bottom using their pelvic fins. 

Juvenile Slender Seamoths are sometimes black.

They grow to 18cms in length.

Slender Seamoths have commercial value for use in Traditional Chinese Medicine.

In Australia Slender Seamoths are found from Fremantle Western Australia around the tropical north, then south to Sydney New South Wales, inhabiting sand or silt bottoms of bays and estuaries.