Largescale Stoneroller
Campostoma oligolepis
Largescale Stoneroller is a small North American minnow that grazes algae and organic films in clear, shallow streams. It is not a common sport fish; anglers usually catch it incidentally while fishing creeks and small rivers.
Identification points
- Large, obvious dark-edged scales that give a rough-looking body
- Small subterminal scraping mouth with thick, hornlike lips
- Olive to brown back with a paler belly and a streamlined minnow shape
Habitat
Clear to slightly turbid warmwater streams and small rivers with riffles, runs, and cobble or gravel bottoms where algae grows on stones; also occurs in pools and margins of moderate-current channels.
Bait notes
Not usually targeted. Small pieces of worm, maggots, or tiny dough/crumb baits will take them; ultra-small jigs or bits of soft plastic can work, but they more often bite while sampling algae-coated cover than chasing lures.
Behavior
A benthic herbivore that scrapes algae and diatoms from rocks with a specialized mouth. It schools in shallow current and is most active where rock surfaces are sunlit and productive; it spawns in spring over gravelly riffles.
Caution
none notable
Fishing notes
Use light line and tiny hooks in shallow riffles, behind rocks, and along current seams. Present baits naturally near the bottom with little weight; they often peck rather than strike hard. Handle gently and release promptly if caught incidentally.