The Freshwater Fish

Fresh waters account for less than 1% of the total water on earth, yet nearly 40% of all living fish are found in fresh water. One reason for this is the diversity of the types of fresh water. Rivers and streams provide very different types of habitats at different elevations. They differ in flow rate, botom type, temperature, pH, dissolved oxygen content, and other chemical factors. Even lakes are quite different, ranging from deep, cold lakes to shallow, sun-warmed lakes.

Class Agnatha

Brook Lamprey
Class characteristics:
link to an Internet Website

One representative of the Family Petromyzontidae has been found in Arizona:

Lamprey life cycle:

Some lampreys need flowing water with a rocky bottom to build a nest, lay their eggs, and spawn. This limits their range to rivers and streams with this characteristic.

Class Osteichthyes

The Apache, or Arizona, Trout Salmo apache, is the Arizona State Fish.

arizona trout

Class characteristics: link to an Internet Website

Trout are probably one of the most widely fished species in Arizona they can be found in many of the streams and lakes of the white mountains and the rim country. Take a look at this link for infromation on many different type of trout. Brook trout




Some common bass found in Arizona are Largemouth, smallmouth and yellow bass. Some other common fish species found in the lakes are walleye, yellow perch, crappie, sunfish, channel catfish and carp. Saguaro Lake is the closest lake to the Phoenix area on the Salt River Chain and contain some of the fish previously mentioned. largemouth bass





Fish identification: fish anatomy

When using a dichotomous key to identify fish, an understanding of the basic body parts is important. There are a number of measurements on the body link to a local picture and head link to a local picture that are important.

fish skull, species unknown The skulls of fish are much different than most other vertebrates. There is no large "skull". The skull is composed of many small bones that are not fused together.

Teeth can clearly be seen on the mandibles and maxillae of this fish. Its species is unknown, but it is obviously a large fish that is not native to Oklahoma.

Research Links: