Temperate perch


Percichthyidae, the temperate perches, are a family of freshwater ray-finned fish found in Australia and southern South America. Formerly placed in the order Perciformes, they are now placed in the order Centrarchiformes.
The name Percichthyidae derives from the Latin perca for perch and Ancient Greek ἰχθύς, ichthys for fish.

Evolution

Potential percichthyid fossil remains are known from the Early Paleocene of the El Molino Formation of Bolivia; these remains have been described as resembling those of the fossil Percichthys hondoensis from the Eocene of Argentina. One articulated specimen is known from the Paleocene portion of the formation, but other remains are known from the Maastrichtian beds of the formation, indicating that percichthyids could have potential Cretaceous origins. However, the condition of this material is unclear. Another fossil percichthyid, Percichthys lonquimayiensis from Chile, was initially dated to the Paleocene, but further studies have found it to be from the Miocene.
Potential percichthyid scales have been recovered from the Miocene-aged fossil deposits of Foulden Maar in New Zealand. If these are of percichthyids, this suggests they had a wider distribution during the Neogene. They also appear to have ranged as far north as the Neotropics during the Oligocene/Miocene, with the fossil genus Santosius known from Brazil.
Modern percichthyids have a significant disjunct distribution, being found in Australia and southern South America. All extant members of the group only inhabit freshwater habitats, and it is thus unlikely they ever evolved marine habits. For this reason, it is likely that the modern distribution of percichthyids derives from dispersal over the Antarctic land bridge between South America and Australia, which existed up to the end of the Eocene. This suggests that percichthyids likely inhabited Antarctica as well.

Classification

The temperate perches are closely related to the freshwater sunfish of North America, with both belonging to the suborder Centrarchoidei. They were previously also thought to be allied with the temperate basses of the family Moronidae and the seabasses in the family Serranidae, but are now thought to not be closely related.
Almost 40 species of percichthyids are now recognised, grouped in 11–12 genera. Most but not all are exclusively freshwater fishes. They are mainly found in Australia, but species are also found in southern South America.
More recently the Chinese perches have been classified in the separate family Sinipercidae while the genus Percilia has been found not to be closely related to either that family or the Percichthyidae and has been placed in its own monotypic family Perciliidae. The two catadromous species in Percalates are found in Australia and were previously placed in Macquaria, but phylogenetic analyses have found them to be the most basal members of the whole order.
The following 8 genera are classified within the family Percichthyidae:
In addition, two extinct genera are known exclusively from fossil remains:
  • †Plesiopercichthys Agnolin et al., 2014
  • †Santosius Arratia, 1982

    Species

Australia has the greatest number of percichthyid species, where they are represented by the Australian freshwater cods, which are Murray cod, Mary River cod, eastern freshwater cod, and trout cod, by the Australian freshwater blackfishes, which are river blackfish and two-spined blackfish, and by the Australian freshwater perches which are golden perch, Macquarie perch, and Australian bass, and estuary perch.
Several other Australian freshwater species also sit within the family Percichthyidae, while research using mitochondrial DNA suggests the species of the family Nannopercidae are in reality percichthyids, as well. Australia is unique in having a freshwater fish fauna dominated by percichthyids and allied families/species. This in contrast to Europe and Asia, whose fish faunas are dominated by members of the Cyprinidae carp family.
A single genus occurs outside Australia, Percichthys in southern South America.
A number of species are or have been important food species; some of these have become threatened through overfishing and river regulation, while others are now farmed to some extent. Some smaller species are popular in aquaria.
The extremely rare Bloomfield River cod, Guyu wujalwujalensis, is only found in a short stretch of the Bloomfield River in north Queensland.

Timeline


ImageSize = width:1000px height:auto barincrement:15px
PlotArea = left:10px bottom:50px top:10px right:10px
Period = from:-65.5 till:10
TimeAxis = orientation:horizontal
ScaleMajor = unit:year increment:5 start:-65.5
ScaleMinor = unit:year increment:1 start:-65.5
TimeAxis = orientation:hor
AlignBars = justify
Colors =
#legends
id:CAR value:claret
id:ANK value:rgb
id:HER value:teal
id:HAD value:green
id:OMN value:blue
id:black value:black
id:white value:white
id:cenozoic value:rgb
id:paleogene value:rgb
id:paleocene value:rgb
id:eocene value:rgb
id:oligocene value:rgb
id:neogene value:rgb
id:miocene value:rgb
id:pliocene value:rgb
id:quaternary value:rgb
id:pleistocene value:rgb
id:holocene value:rgb
BarData=
bar:eratop
bar:space
bar:periodtop
bar:space
bar:NAM1
bar:NAM2
bar:NAM3
bar:space
bar:period
bar:space
bar:era
PlotData=
align:center textcolor:black fontsize:M mark: width:25
shift:
bar:periodtop
from: -65.5 till: -55.8 color:paleocene text:Paleocene
from: -55.8 till: -33.9 color:eocene text:Eocene
from: -33.9 till: -23.03 color:oligocene text:Oligocene
from: -23.03 till: -5.332 color:miocene text:Miocene
from: -5.332 till: -2.588 color:pliocene text:Plio.
from: -2.588 till: -0.0117 color:pleistocene text:Pleist.
from: -0.0117 till: 0 color:holocene text:H.
bar:eratop
from: -65.5 till: -23.03 color:paleogene text:Paleogene
from: -23.03 till: -2.588 color:neogene text:Neogene
from: -2.588 till: 0 color:quaternary text:Q.
PlotData=
align:left fontsize:M mark: width:5 anchor:till align:left
color:paleocene bar:NAM1 from: -58.7 till: -55.8 text: Palaeopercichthys
color:eocene bar:NAM2 from: -55.8 till: 0 text: Percalates
color:miocene bar:NAM3 from: -23.03 till: 0 text: Maccullochella
PlotData=
align:center textcolor:black fontsize:M mark: width:25
bar:period
from: -65.5 till: -55.8 color:paleocene text:Paleocene
from: -55.8 till: -33.9 color:eocene text:Eocene
from: -33.9 till: -23.03 color:oligocene text:Oligocene
from: -23.03 till: -5.332 color:miocene text:Miocene
from: -5.332 till: -2.588 color:pliocene text:Plio.
from: -2.588 till: -0.0117 color:pleistocene text:Pleist.
from: -0.0117 till: 0 color:holocene text:H.
bar:era
from: -65.5 till: -23.03 color:paleogene text:Paleogene
from: -23.03 till: -2.588 color:neogene text:Neogene
from: -2.588 till: 0 color:quaternary text:Q.