Blue Sucker
  • Side view adult.
  • Side view adult.
  • Side view adult.
  • Top view adult.
  • Bottom view adult.
  • Head-on view adult.
  • Close-up flank.
  • Close-up head.
  • Close-up mouth and snout.
  • Close-up tail.
  • Close-up dorsal fin.
  • Close-up anal fin.
  • Close-up pectoral fin.
  • Close-up pelvic fin.
  • Close-up head: The mouth is inferior.
  • Close-up mouth/snout: The lips are fleshy and papilose.
  • The body shape is elongated and fusiform, the color is bluish; there are 53-58 lateral line scales and 28-33 dorsal rays.
  • Close-up dorsal fin: There are 28-33 dorsal rays with anterior rays being elongated.
  • Breeders develop numerous turbercles on their fins and bodies.
  • Breeders develop numerous turbercles and a dark color on their bodies; specimen held by Kyle Piller.
  • Breeders develop numerous turbercles on tail and scales.
  • Breeders develop numerous turbercles on their heads.
  • Juveniles are similar to adults, but lower lobe of caudal fin is darker.
  • Side view of the largest confirmed specimen from Wisconsin (weight 7.5 kg).
DescriptionSimilar Species
Family
Suckers (Catostomidae)
Body
Mouth and snout: Inferior, no teeth on jaws. No barbels. Body patterning, color, and scales: Solid colors. Body usually dark gray or blue-black, but sometimes a dark reddish brown or a lighter blue-gray, with cream on the belly. Fins darkly pigmented. 53-58 cycloid lateral line scales. Body shape and size: Body fusiform and elongate; oval in cross section. Typically 600-750 mm (24-30 in) TL; maximum in Wisconsin about 900 mm (36 in).
Fins
Tail, dorsal and other fins: Forked tail. Single dorsal with no spines and 28-33; anterior rays somewhat elongated. Pelvic fins abdominal. Adipose fin absent. Anal fin with 7-8 (usually 7) rays.
Distinguishing Characteristics
The blue sucker is unique in having more than 25 dorsal rays, the anterior ones elongated, more than 50 lateral line scales, and an elongated fusiform body. See also similar species information.
Breeding Adults
Males with numerous small tubercles over head, scales, and fins, often very dark colored.
Juveniles
Very small young of the year have the lower caudal lobe darkly pigmented and the upper lobe clear. Larger juveniles are similar to adults.
Hybrids
None
Compare Similar Species
Dorsal Fin
Redhorse, Black12-14 rays, margin concave or falcate, rarely straight
Redhorse, Golden10-15 rays, usually 13, margin concave or falcate, rarely straight
Redhorse, Greater11-15 rays, usually 13-14, margin slightly concave to slightly convex
Redhorse, River13-15 rays, margin straight or slightly concave
Redhorse, Shorthead11-15 rays, usually 12-14, margin falcate
Redhorse, Silver14-17 rays, usually 15, margin usually straight or slightly convex
Sucker, Blue28-33 rays, anterior rays elongated
Sucker, Longnose9-11 rays, marging straight to slightly concave
Sucker, Northern Hog9-12 rays, usually 11-12, margin falcate
Sucker, Spotted11-12 rays, margin straight to falcate
Sucker, White10-13 rays, margin slightly concave to slightly convex
Lower Lip
Redhorse, BlackObtuse angle or straight margin, plicate
Redhorse, GoldenObtuse angle, plicate
Redhorse, GreaterObtuse angle, plicate
Redhorse, RiverObtuse angle or straight margin, plicate
Redhorse, ShortheadStraight margin, plicate with a few papillae
Redhorse, SilverAcute or right angle, papillose
Sucker, BlueAcute angle, papillose
Sucker, LongnoseAcute angle, papillose
Sucker, Northern HogAcute angle, papillose
Sucker, SpottedObtuse angle, relatively thin, plicate
Sucker, WhiteAcute angle, papillose
Body Pattern
Redhorse, BlackSolid color
Redhorse, GoldenSolid color
Redhorse, GreaterSolid color or with faint spots at anterior base scales in some fish
Redhorse, RiverSolid color or with faint spots at anterior base scales in some fish
Redhorse, ShortheadSolid color or with faint spots at anterior base scales in some fish
Redhorse, SilverSolid color
Sucker, BlueSolid color, darkly pigmented
Sucker, LongnoseSolid color or faint blotches, breeders with lateral stripe
Sucker, Northern HogDark mottling and large dark irregular blotches
Sucker, SpottedDark spots at anterior base of scales; lateral stripes in some breeders
Sucker, WhiteSolid color or faint blotches, breeders with lateral stripe
Lateral Line Scales
Redhorse, Black43-51, usually 44-47, all pored
Redhorse, Golden37-45, usually 40-42, all pored
Redhorse, Greater41-45, usually 42-44, all pored
Redhorse, River41-46, usually 42-44, all pored
Redhorse, Shorthead39-46, usually 42-44, all pored
Redhorse, Silver38-46, usually 41-42, all pored
Sucker, Blue53-58, all pored
Sucker, Longnose91-115, usually >95, all pored
Sucker, Northern Hog46-54, usually 47-51, all pored
Sucker, Spotted42-46, 0-38 pored
Sucker, White55-85, usually 60-70, all pored
Other Characteristics
Redhorse, BlackPelvic rays 8-11 but almost always one or both with 10; caudal peduncle depth >59% of caudal peduncle length; tail slate-colored in life
Redhorse, GoldenPelvic rays 9; caudal peduncle depth usually >63% of caudal peduncle length; tail slate-colored in life
Redhorse, GreaterHead rounded with a rounded snout, not overhanging lips ventrally; tail orange or red in life; scales around caudal peduncle 15-16
Redhorse, RiverHead rounded and bulky with a blunt or slightly rounded snout, overhanging lips ventrally in adults; tail orange or red in life; scales around caudal peduncle 12-13
Redhorse, ShortheadHead tapered to a pointed or slightly blunt snout, not overhanging lips ventrally; tail orange or red in life; scales around caudal peduncle 12-13
Redhorse, SilverTail slate-colored in life
Sucker, BlueDarkly pigmented fins
Sucker, LongnoseSnout distinctly extends past upper lip
Sucker, Northern HogTop of head with concavity between eyes; other species have this area flat or convex
Sucker, SpottedSpotes lined up in horizontal rows; limited to area above anal fin in small juveniles
Sucker, WhiteSnout barely extends past upper lip
Similarity Index
Redhorse, BlackModerately similar
Redhorse, GoldenModerately similar
Redhorse, GreaterModerately similar
Redhorse, RiverModerately similar
Redhorse, ShortheadModerately similar
Redhorse, SilverModerately similar
Sucker, BlueN/A
Sucker, LongnoseModerately similar
Sucker, Northern HogModerately similar
Sucker, SpottedModerately similar
Sucker, WhiteModerately similar
Login