Creek loach is a species of ray-finned fish in the genus Schistura.
identification of the Tulalip Creek loach I wrote about in http://www.nanfa.org/reg_spot/Loach99/LoachHunt99.htm as Misgurnus anguillicaudatus. As you can see in his message appended below, he mentions that another M. anguillicaudatus was recently found in the lower Columbia River. More
I believe the Tulalip Creek loach is one of these two loaches, and most likely M. anguillicaudatus. Photos I've seen on the Internet and in aquarium fish books have been rather unhelpful in identifying this fish, but it does appear to be of the genus Misgurnus. More