Moxostoma anisurum
Silver Redhorse

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The natural history of the northwoods



  • Moxostoma, from the Greek, "mouth to suck"
  • anisurum, from the Greek, "unequal tail"
  • Common name from silvery sides and belly
  • Other common names include: Bay Mullet, Longtailed Sucker, Redfin Mullet, Silver Mullet, Silver Sucker, White Nose Redhorse, White Sucker


  • Kingdom Animalia
    • Phylum Chordata, animals with a spinal chord
    • Subphylum Vertebrata, animals with a backbone
      • Superclass Osteichthyes, bony fishes
      • Class Actinopterygii, ray-finned and spiny rayed fishes
      • Subclass Neopterygii
      • Infraclass Teleostei
        • Superorder Ostariophysi
        • Order Cypriniformes, minnows and suckers
          • Family Catostomidae, suckers
            • Genus Moxostoma, the redhorses


  • A chunky, coarse-scaled sucker.
  • Length l0"-20"
  • Weight
    • typically ½ to 3½ lbs
    • up to 14 lbs
  • Coloration
    • darker above
    • sides pale, silvery
    • bright silver below
    • tail fin olive or slate-colored with pale silvery sides
  • Body
    • short dorsal fin of 14/15 soft rays
    • air bladder of three chambers
  • Head
    • head and eyes large
    • mouth small
    • rear margin of thin lower lip forms acute, V-shaped angle, covered with numerous small, wart-like bumps (papillae)
    • no teeth in the mouth, pharyngeal teeth in the throat.
  • Lifespan to14 years.


  • Closely resembles Golden Redhorse (Moxostoma erythrurum), and often mistaken for each other.
  • Distinguished from other redhorses by the presence of 14/15 (occasionally 16) soft rays in a short dorsal fin with straight or slightly curved outer margin.


  • Hudson Bay to Alberta; south to Georgia
  • Not known from the Lake Superior drainage of the eastern BWCA


  • Prefers deep water habitat.


  • Aquatic insect larvae, crustaceans, small mollusks, and some plant material.
  • Bottom feeders.


  • Minnesota Record: 7 lbs 9 oz, Rainy River (Koochiching County).
  • Appears to be less abundant than formerly, though records sketchy.



  • Spawns earlier in the year than most redhorses, peaking in April at water temperatures of 56 º F.
  • Fish ascend small tributary streams where they congregate in large schools.
  • Preferred spawning habitat is shallow riffles up to 3' deep over gravel or rubble bottoms.
  • Semi-adhesive eggs are scattered at random to hatch unattended after 7-l0 days. A mature, moderate sized female will produce about l5,000 eggs.
  • Sexual maturity occurs late in life at age 4 or 5.



Boreal border

Last updated on 6 November 1999