Yes, Sam, a mudcat is a type of catfish. It's more of a colloquial term than an official one (like, say, channel cat) and probably won't be found in an encyclopedia.

The lack of scales on catfish is interesting. A traditional way to skin them is to nail the fish to a tree or board by the head, slit the skin at the neck, and peel it off the body, much as one might peel off a stocking. Looks wierd, but works beautifully.

Catfish (at least some types), cooked properly (usually lightly breaded and fried), are delicious. Some people look down on them as food, calling them "bottom feeders", but here in the Midwest (Missouri, Arkansas, etc.) they are well loved.