New species of ugly big-headed fish discovered in Idaho and Montana rivers

Say hello to the cedar sculpin, a previously unknown species of fish that was recently discovered living in the rivers of Idaho and Montana.

Researchers working at the U.S. Forest Service Rocky Mountain Research Station stumbled upon this rather homely little fellow — a species of bottom-dwelling freshwater sculpin — when they were taking stock of the species that were living in the Columbia River basin. It wasn't clear that it was actually a new species at first, since it looks very similar to another type of sculpin that lives in the area, called the shorthead sculpin. However, a comparison of the physical characteristics of both and an analysis of their DNA confirmed it.

"The discovery of a new fish is something I never thought would happen in my career because it's very rare in the United States," Michael Young, a research fisheries biologist with the U.S. Forest Service, told Reuters.

The differences between this species and its distant relation are fairly minor at first glance — slightly different measurements of their head and pelvis, and differences in the arrangement of a row of pores between their anal fin and their tail fin. They also have a small, skin-covered spine just in front of their gills, and while many species of sculpin have these 'preopercular spines,' this is apparently something the other species of sculpin in the area don't have.

The cedar sculpin and its relatives may not be much to look at, but they're a valuable part of the local river ecology. There's a large focus on them as being a favourite food of sport fish like trout, thus their value to anglers. In fact, there are even fishing flies (like this one) designed after them.

However, there has been a call in recent years for the focus to switch from sport fish to the sculpin as the representatives for conservation efforts. With the high number of species, and their tendency to have the largest populations of small fish in any particular ecosystem, keeping them healthy would mean keeping the entire ecosystem healthy.