The flathead galaxias (''Galaxias rostratus'') is a
freshwater fish found in
lowland rivers,
stream
A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. Depending on its location or certain characteristics, a stream ...
s and associated
billabongs,
backwaters, and
wetlands of the southern
Murray-Darling river system in southeastern
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...
.
Flathead galaxias continue a pattern of speciation into
upland
Upland or Uplands may refer to:
Geography
*Hill, an area of higher land, generally
*Highland, an area of higher land divided into low and high points
*Upland and lowland, conditional descriptions of a plain based on elevation above sea level
*I ...
and
lowland habitats found in native Murray-Darling fishes. Flathead galaxias are found in lowland habitats, while the
mountain galaxias species complex, containing at least seven species of ''Galaxias'' (research is ongoing) are found in upland habitats, as well as "midland" or upland/lowland transitional habitats.
Morphology
The fish is similar in appearance to the
common galaxias, except for a distinctly flattened head, larger eyes and longer snout.
It has an olive green back and sides with indistinct grey to green blotches and silvery bottom. Adults are commonly in length, but have been found to be up to long.
Conservation
Serious concerns exist for flathead galaxias. They, along with a number of other small native
forage fish, are disappearing from vast tracts of the Murray-Darling basin. The species is considered
extinct
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
in South Australia.
Along with river regulation, destruction of water clarity and submergent macrophytes ("water weed") by exotic, illegally introduced
common carp
The Eurasian carp or European carp (''Cyprinus carpio''), widely known as the common carp, is a widespread freshwater fish of eutrophic waters in lakes and large rivers in Europe and Asia.Fishbase''Cyprinus carpio'' Linnaeus, 1758/ref>Arkive The ...
(''Cyprinus carpio'') appear to be having a devastating effect on this species. Many or all of the small native forage fish of the southern Murray-Darling system apparently used these weeds beds for shelter, feeding, and spawning sites.
References
*
*
External links
Native Fish Australia - Flathead Galaxias page
{{Taxonbar, from=Q4848085
flathead galaxias
Fish of the Murray-Darling basin
Vulnerable fauna of Australia
Taxa named by Carl Benjamin Klunzinger
flathead galaxias