Perches and Perch-like fish are part of the order Perciformes. This order contains over 10,000 species. Popular aquarium inhabitants in this large order include freshwater cichlids, gouramies, and wrasses. It also includes marine tangs, rabbitfish, and damsels; as well as freshwater and/or brackish water scats, gobies and live-bearing anabantids, to name just a few.
The fish included here are members of the Sub-Order Percoidei the "perch-like" fishes. This is one of 18 Sub-orders belonging to the Perciformes order. There are about 81 families in this sub-order and over 3,100 species. The Percoidei families have traditionally been grouped together because they showed no great morphological specialization. They live in a variety of habitats and have variable functions and behaviors, but they were not greatly differentiated anatomically. As more is learned about the distinctive physical traits of different families, the scientific classification is being re-structured, but it is in a state of flux.
The Percoidei fishes are typically found in tropical areas. The majority are found in saltwater environments though some are brackish water fish and others are freshwater fish. They occupy shore or coastal waters with very few being pelagic, or open water dwellers. Many are harvested as food fish and some species are enjoyed by aquarists.
Many favorite brackish water aquarium specimens are Perches and Perch-like fish, and a few are freshwater. The fish included here that are members of the suborder Percoidei include the Glassfish, Mono or Fingerfish, Archerfish, Scats, True Perches, Datnoids, Sunfish, Cardinalfish and others. Though many of these are brackish water fish, not all are, so be sure to see the fish guide for each species to find its particular water conditions. Perch-like fish that are strictly marine fish will be found in the Saltwater Fish sections.
The Perch types list below includes popular species, as well lesser known Perch-like varieties. Each fish guide has a description of the species, its place of origin, habitats and behaviors, as well as fish care to successful maintain them in an aquarium. Fish pictures are also provided within each fish guide to help with identification, and to aid in choosing the best type of Perch-like fish for your freshwater or brackish water fish tank.
The Perch and Perch-like fish are members of the Order Perciformes. Perch and Perch-like fishes have been grouped in the Sub-order Percoidei, which is one of 18 sub-orders belonging to the Perciformes Order. Perciformes is an order of fishes belonging to the class of "ray-finned" fish. The Perciformes order is the largest order of fishes. It contains about 40% of all bony fish with more than 160 families and over 10,000 species. These are some of the most variable fish in size, ranging from 1/4 of an inch (.28 cm) to a whopping 16 feet (5 m), and they are found in all aquatic environments.
Most perciforms are shore or coastal water fish. The majority are marine fishes but about 2,000 species normally occur only in freshwater. About 2,200 species are brackish water types, because they live in freshwater for at least part of their lives.
The perch-like fish have long been grouped together in the the Sub-order Percoidei because they were not greatly differentiated anatomically. There was no great morphological specialization known, even though they may live in a variety of different habitats and have variable functions and behaviors. As more is learned about each of these types of fish, there are suggested taxonomy and classification restructures. This is discussed in more detail under "Perch Classification" below.
Perch-like Fish Families
There are many families of perch-like fish, at least 80 families, but not all of these are found in the aquarium hobby. Yet there are some very fascinating perch type fish that are readily available and some others that are an occasional exciting find. Many of these are also seen when scuba diving! Descriptions of the most well-known families of perches and basses, as well as some other familiar families are included here:
Family: Ambassidae - Asiatic Glassfish (also known as the Chandidae)
The Glassfish, like their name implies, are transparent and you can see their backbone and swim bladder. The dorsal fin is usually divided and the lateral line extends to the tail fin. They have ctenoid scales, meaning they are tough with a toothlike margin. These fish are found in either saltwater or brackish water.
Family: Apongonida - Cardinalfish
This is a fairly small family of fishes with the largest species reaching only up to about 8 inches (20 cm) in length. They mostly live as schooling fish in the tropical and subtropical seas of the Indo-Pacific, but a few species live in freshwater. They have two dorsal fins, the first being entirely made up of hard spines and usually two spines on the tail fin. They have fairly large ctenoid scales, meaning they are tough with a toothlike margin. Many species care for their young with the eggs and fry both taken in the mouth of the male, but sometimes also by the female.
Family: Badidae - Chameleon Fish
This is a more recently establish family with just one genus and one species known as the Badis, Dwarf Chameleon Fish or Blue Perch, Badis Badis.This genus is similar to the Leaffishes in the Nandidae Family, but has just enough differences to be placed in its own family. It differs from the Leaffishes because of its very small mouth and being unusually colorful, has some morphological and behavior differences, and has no labyrinth organ.
Family: Centrarchidae - SunFish
The Sunfish are mostly egg-shaped with flattened sides, though some are elongated. The dorsal and anal fins have two sections, hard-rays on the front and soft-rays on the back. All species in this family care for their young, with the male being particularly watchful over the eggs. Most form a patriarchal family, though one genus Micropterus, forms a nuclear family. The young fish can be very brightly colored, but they may pale as they mature.
Family: Centropomidae - Giant Perches or Snooks
This is a family that has gone through some major changes since 2004. It used to contain the Glassfish as well as large perches that are now in the family Latidae. Now has only 1 genus, Centropomus, and about 12 species that are either freshwater fish or marine fish. These fish have been favored as a food fish, and are found in tropical and subtropical waters from the western Atlantic to the eastern Pacific oceans.
Family: Lobotidae - Tripletails or Flashers
There is one genus in this family, Lobotes, and not many species in the genus. They are mostly found in South-east Asia in large brackish water estuaries. They are tall laterally compressed fish, generally with a mottled patterning in browns and golds.
Family: Kuhliidae - Flagtails
This is a small family, with barely a dozen species found in the Indo-Pacific. Most are saltwater fish, but some species will inhabit brackish water or even freshwater, like the Rock Flagtail Kuhlia rupestris. These fish are similar in body shape to the Sunfish, but are slender and the body and head are covered with medium sized ctenoid scales, meaning they are tough with a toothlike margin. They have a divided dorsal fin with the front one having hard-rays and the back one having soft rays.
Family: Kurtidae - Humpheads or Nurseryfish
These are a medium sized perch fish, reaching a maximum length of about 23 1/2 inches (60 cm). There is only one genus in this family, Kurtus, and two species. These fish are found in coastal waters and the mouths of rivers from India, Thailand, Malaysia, and Indonesia to China. They will inhabit saltwater, brackish water and sometimes in freshwater. These fish have a very laterally compressed body that is covered with small round scales and a long strong rib structure, making it look encased in armor. Yet the head is almost naked. The dorsal fin is very broad, with many rays. On mature specimens they develop what looks like a serrated comb on the nape of the neck.
Family: Lutjanidae - Snappers
There are about 16 genera containing around 100 species of fish in this family. They are found in all the oceans of the world with the exception of the eastern Pacific. They inhabit tropical and subtropical regions. Most are strictly saltwater fish, but there are some that will venture into estuaries and even feed in freshwater. They are identified by their typical triangular shaped head. On most of these fish, the dorsal fin is not divided into two, but they do have a hard-ray portion in the front and a soft-ray portion to the back half of the fin. They differ from the Serranidae family of Sea Basses and Groupers by having 10 hard-rays, pointed pectoral fins, and a tail fin that is usually forked. There are several that are important food fish, but because these fish will feed on poisonous algae they can have a high concentration of accumulated toxins.
Family: Monodactylidae - Mono, Fingerfish, or Moonyfish
There are three species of Mono that are wonderful, popular aquarium fish. Two, Monodactlyus argenteus, Monodactylus kottelati, are commonly called Mono or Malayan Angel and the other is the West African Mono Monodactylus sebae. These fish have flat, disc shaped bodies with a small head and mouth. Their dorsal and anal fins are similar in shape and usually erect, giving them an "angelfish" appearance. They have small ctenoid scales, meaning they are tough with a toothlike margin. These are a schooling fish generally from brackish waters, though periodically may be found in freshwater.
Family: Moronidae - Temperate Basses
This family is very similar to the Percichthyidae family of Temperate Perches, and are also similar to the Sea Basses of the Serranidae family, though they differ in appearance. They are an important food fish, found near coastal regions of North America and Europe.
Family: Nandidae - Leaffish
The Leaffish come from South America, Africa, and south-east Asia. They are oval, in the general shape of a leaf, thus their common name. They are generally small fish with a large head and mouth, and the mouth open very wide. They have large ctenoid scales, meaning they are tough with a toothlike margin. All of these fish are predators and all but one species form matriarchal families, carefully caring for their brood.
Family: Percichthyidae - Temperate Perches
This family is very similar to the Moronidae family of Temperate Basses, and are also similar to the Sea Basses of the Serranidae family, though they differ in appearance. There are about 11 genera and most are saltwater fish. They are found in South America and as far north as California, and from Australasia to Asia. These are an important food fish.
Family: Percidae - True Perches
These fish have two broad, often divided dorsal fins. These fish have a large head and two nostrils on each side. The front dorsal has spiny rays while the back one has soft-rays. They have pelvic fins that extend from the stomach. They have ctenoid scales, meaning they are tough with a toothlike margin.
Family: Scatophagidae - Scats or Argus Fish
The Scats are another wonderful and popular aquarium fish. These fish are found in coastal areas of Asia and Australia, both is the ocean and brackish waters, and may occasionally enter fresh water. They have flat, disc shaped bodies. The head, body and soft-rayed portions of the fins are covered with small ctenoid scales, meaning the scales are tough with a toothlike margin. They young may go through a larval or "Tholichthys" stage, where its body is covered in large bony plates that they then loose as they mature.
Family: Serranidae - Sea Basses and Groupers
There are about 450 species in this family, contained in 64 genera. Most of these are saltwater fish that are found primarily in tropical waters, though some species live in temperate seas. This is a very diverse group in terms of size, they can range from about 3/4 inches (2 cm) in length and weigh next to nothing, to very large fish that can reach up to 7 3/4 feet (2.4 m) and weight over 660 lbs (300 kg)! These fish have a stout body with a large head and good sized mouth. They have two dorsal fins, and the one in front has strong spines. Most of these fish are protogynous hermaphrodites, meaning they are female when young and then may become male as they mature.
Family: Terapontidae (also spelled Theroponidae) - Grunts and Tiger Perches
This is a small family that has a wide range in the Indo-Pacific region and many species will enter freshwater occasionally. They can be found from the east African coast to the Red Sea to Australia as well as some of the west Pacific Islands. They are similar to the Sea Basses and many are used as a food fish. But they differ in that they have fewer dorsal rays, smaller mouths, and their teeth are serrated.
Family: Toxotidae - Archerfish
The Archer fish are a familiar aquarium fish that are found in the brackish coastal waters of Asia and northern Australia. Their are five species in the Toxotidae family, and they are all surface dwellers. They are quickly recognized by their pointed heads with a big mouth and large eyes. They have a straight lateral line and the dorsal and anal fins start way back on the body towards the tail. They have luminous, reflecting patches of iridescent yellow on their bodies, and will signal each other with them. Sometimes the patches fade with age. These fish gained their popular name by their ability to expectorate drops of water above the surface, bringing down insects to feed on.
Perch and Perch-like fishes belong to the Sub-order Percoidei of "perch-like" fishes. This sub-order has about 81 families with over 3,100 species. The ITIS Interagency Taxonomic Information System currently places all families of the The Sub-Order Percoidei, as direct children.
ITIS does not further divide the Percoidei sub-Order beyond the family level. However, taxonomy is in a state of flux, with ongoing suggested changes to the classification structure. There are other classifications evolving that suggest defining the families of the Percoidei Sub-Order beyond what ITIS does following Joseph S. Nelson' s book, Fishes of the World, Wiley, 2006.
In this alternate classification structure, most of the fish families included in the Percoidei Sub-Order are members of the Superfamily Percoidea. However, a few families are placed in other suborders, and some are placed in new orders. The Sub-Order: Percoidei with new divisions are shown in the chart below:
Perch -like Fish
Order: Perciformes = Families in the Sub-Order: Percoidei