The standard name for this fish is akamutsu. The mutsu in it is misleading, because it is not a mutsu at all but a member of the Acropomatidae, a different family entirely.

Nodoguro, the name everyone actually uses, means black throat. Open the mouth and the back of it is black, a thin dark membrane stretched across the inside. It lives in the Sea of Japan at depths of a hundred to two hundred meters, and off Ishikawa the Tsushima current meets cold deep water, which is the kind of boundary that produces good fishing. The catch comes ashore at Kanazawa and at Hashidate, taken by bottom trawl or on a line.

The number that explains this fish is its fat content. A white-fleshed fish generally runs to a few percent. This one can pass twenty, which is why people call it the toro of white fish. The season given is autumn through winter, though it is also said that the flavor holds up more or less all year.

Salt it and put it over the heat and the skin tightens and pulls, and the fat starts coming out of the flesh and dropping. You can hear it landing underneath while the fish is still cooking, which tells you what is happening before you have tasted anything. It is a fish of about forty centimeters, with the fat carried right through the flesh rather than sitting in one layer.