Pylodictis is Greek meaning "mud fish," and olivaris is Latin for "olive-colored." Flathead catfish are typically pale yellow (hence the name "yellow cat") to light brown on the back and sides, and highly mottled with black and/or brown. The belly is usually pale yellow or cream colored. The head is broadly flattened, with a projecting lower jaw. The tail fin is only slightly notched, not deeply forked as is the case with blue and channel catfish. Young fish may be very dark, almost black in appearance.
The flathead catfish is the second largest freshwater sportfish in Texas, being outmuscled only by the blue catfish. Where mature populations exist, 50-pounders are not unusual. Typically, the largest fish are caught by trotliners, who have landed specimens in excess of 110 pounds. "Catfish" is the second most preferred group of fish among licensed Texas anglers, and flatheads rank second behind channel catfish. Rod and reel anglers may have the greatest success with flathead catfish just below reservoir dams.
In Texas flathead catfish may spawn from late May through August. Males construct nests by excavating a shallow depression in a natural cavity (a hollow log, cave, or crevice) or near a large object. Females are encouraged by males to lay their eggs in the nest. Over 100,000 eggs may be found in a golden-yellow egg mass which is guarded viciously by the male. Young generally hatch in four to six days. They may school together for several days near the nest, but soon disperse and seek shelter under rocks or brush. Fingerlings feed on insect larvae, juveniles feed on small fish and crayfish, while adults feed almost exclusively on fish. Adults are usually solitary, each staking out a favorite spot, typically in deeper water or under cover, during the day. At night they may move into riffles and shallow areas to feed.
The native range includes a broad area west of the Appalachian Mountains encompassing large rivers of the Mississippi, Missouri, and Ohio basins. The range extends as far north as North Dakota, as far west as New Mexico, and south to the Gulf including eastern Mexico. Flathead catfish occur statewide in Texas.