The bullrout (''Notesthes robusta''), also commonly called freshwater stonefish or kroki, is a pale yellowish to dark-brown coloured

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

that lives in tidal

estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environment ...

and slow-flowing streams in eastern Australia, from Southern

New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

to northern

Queensland, Australia ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

.
It has on a very infrequent occurrence been caught at sea. Its spines are venomous. It is the only member of the genus ''Notesthes''.

Taxonomy and etymology

The bullrout was first formally described in 1860 as ''Centropogon robustus'' by the German-born British

herpetologist Herpetology (from Greek ἑρπετόν ''herpetón'', meaning "reptile" or "creeping animal") is the branch of zoology concerned with the study of amphibians (including frogs, toads, salamanders, newts, and caecilians (gymnophiona)) and rept ...

and

ichthyologist Ichthyology is the branch of zoology devoted to the study of fish, including bony fish ( Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 33,400 species of fish had been described as of Octobe ...

Albert Günther Albert Karl Ludwig Gotthilf Günther FRS, also Albert Charles Lewis Gotthilf Günther (3 October 1830 – 1 February 1914), was a German-born British zoologist, ichthyologist, and herpetologist. Günther is ranked the second-most productive re ...

with its type locality given as

. The genus ''Notesthes'' was described in 1903 by the Australian ichthyologist

James Douglas Ogilby James Douglas Ogilby (16 February 1853 – 11 August 1925) was an Australian ichthyologist and herpetologist. Ogilby was born in Belfast, Ireland, and was the son of zoologist William Ogilby and his wife Adelaide, née Douglas. He received h ...

as a monotypic genus for the bullrout. This taxon is included in the subfamily Tetraroginae within the Scorpaenidae in the 5th edition of ''

Fishes of the World ''Fishes of the World'' by the American ichthyologist Joseph S. Nelson (1937–2011) is a standard reference for fish systematics. Now in its fifth edition (2016), the work is a comprehensive overview of the diversity and classification of the ...

'' however other authorities place that subfamily within the stonefish family

Synanceiidae Synanceiinae is a subfamily of venomous ray-finned fishes, waspfishes, which is classified as part of the family Scorpaenidae, the scorpionfishes and their relatives. These fishes are found in the Indo-Pacific oceans. They are primarily marin ...

, while other authorities classify this subfamily as a family in its own right. The genus name ''Netesthes'' combines ''notos'', which means

back The human back, also called the dorsum, is the large posterior area of the human body, rising from the top of the buttocks to the back of the neck. It is the surface of the body opposite from the chest and the abdomen. The vertebral column run ...

, and ''esthes'', meaning "a garment", an allusion to the completely scaled back of this taxon. The specific name ''robusta'' means "stout" or "full-bodies" and allusion Günther did not explain but which maybe to its more robust body shape when compared to what was thought to be the closely related Eastern fortescue (''Centropogon australis'').

Description

The bullrout is big headed with bony ridges, a large mouth and a lower jaw which protrudes beyond the upper jaw. There are 7 spines on the operculum. There are 15 robust spines in the

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ...

and this part of dorsal fin is slightly concave towards the rear with the rearmost soft ray in the dorsal fin being attached to the caudal peduncle by a membrane. The head has no scales but the body is clothed in small scales. The overall colour is pale yellowish to dark brown broken by dark reddish-brown to greyish or black irregular mottling which can coalesce to create irregular bands. The maximum recorded

standard length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish m ...

is , although a standard length of is mor typical.

Distribution and habitat

The bullrout is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to eastern Australia where it occurs from north of

Cooktown, Queensland Cooktown is a coastal town and locality in the Shire of Cook, Queensland, Australia. Cooktown is at the mouth of the Endeavour River, on Cape York Peninsula in Far North Queensland where James Cook beached his ship, the Endeavour, for repairs ...

south to Pambula, southern New South Wales. This fish lives in the lower freshwater stretches of rivers and streams, as well as in bays and estuaries. It is typically encountered within aquatic vegetation or woody debris in still or slow flowing freshwaters where there are rocky, muddy or gravel substrates.

Biology

The bullrout is a rather sedentary species in which individuals spend most of the time lying in wait on the bottom or among weeds for prey to pass, it is an

ambush predator Ambush predators or sit-and-wait predators are carnivorous animals that capture or trap prey via stealth, luring or by (typically instinctive) strategies utilizing an element of surprise. Unlike pursuit predators, who chase to capture prey us ...

feeding on fishes and small crustaceans. They are known to migrate downstream in rivers during periods of heavy rainfall. They breed in freshwater and juveniles have been recorded from the upper reaches of rivers, upstream from barriers.

Danger to humans and first aid

The dorsal, anal, and pelvic spines on a bullrout have venom glands on them, and should be handled with extreme care.

References

External links

Fishes of Australia : ''Notesthes robusta''
{{Taxonbar, from=Q2479457 Tetraroginae Venomous fish Marine fish of Eastern Australia Fish described in 1903 Taxa named by Albert Günther