Like its fish cousins, flathead catfish are noted for their whisker-like barbels around the mouth and scaleless skin. This particular breed, however, has a flat head — as the name suggests — that sets it apart from other types of catfish. A true flathead also can be marked by its projecting lower jaw, in addition to a slightly notched tail fin. Flatheads — sometimes referred to as a yellow cat, opelousas or shovelhead cat — can grow as long as 4 feet (about 1.2 meters).
Some of the larger varieties weigh upwards of 100 pounds (about 45 kilograms). In terms of physical appearance, flathead catfish typically have a pale yellow appearance, hence the nickname yellow cat. Depending upon the variation, they also can have an olive or light brown tint to their skin, though at infancy their appearance can be much darker. In most instances, a flathead's stomach region is cream colored or pale yellow. Other characteristics include sharp spines on the back and shoulder fins.
In addition to the few notable physical features, flathead catfish differ in terms of their eating habits as well. They are far more finicky than other types of catfish, which are oftentimes deemed scavengers. Flatheads live solely on live fish. A typical meal for an infant flathead consists of crayfish, insects and worms. As they grow into adulthood, they begin to eat such species as largemouth bass, other catfish — including fellow flatheads — sunfish and carp.
Flathead catfish can live in a variety of climates; for this reason they are native to a number of bodies of water throughout North America, from as far north as the lower Great Lakes region to as far south as the northern portion of Mexico. Mating season for a flathead is generally between May and August, when water temperatures range between 75 and 80 degrees Fahrenheit (23 to 27 degrees Celsius). According to water biologists, flatheads in optimal living conditions have a life expectancy ranging from 12 to 14 years.
Throughout most of their lives, flathead catfish tend to swim in solitude. This is in direct contrast to other types of fish that swim in schools, or groups — oftentimes in unison with one another. The one notable exception for a flathead is during the fry stage. Young flatheads typically band together for a few days after hatching, but eventually go off on their own, seeking shelter from prey as they sojourn on to their adult lives.