Suckermouth Minnow
  • 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 mouth: The mouth is inferior with fleshy lips.
  • Close-up mouth: The mouth is inferior with fleshy lips.
  • Close-up tail: Notice the caudal spot.
  • The suckermouth minnow has a thin lateral stripe, 43-51 lateral-line scales, a caudal spot, and an inferior mouth.
  • Close-up head region of a breeding male: Notice the small tubercles on head, nape, and pectoral fins.
  • Side view of a breeding male: Breeding males have a darker, more conspicuous lateral stripe.
  • Side view of a young-of-year: Juveniles are similar to adults.
DescriptionSimilar Species
Minnows (Cyprinidae)
Mouth and Snout: Mouth inferior without any teeth. No barbels. Thick fleshy lips with plicae and pappilae. No frenum connecting snout with upper lip. Body Pattern: Sides silvery, gray, or brown with a dark lateral stripe (sometimes faint) and a spot at the base of the tail; white belly. Pectoral, caudal, and dorsal fins pigmented; pelvic and anal fins whitish. Cyloid scales. Body Shape: Fusiform, almost round in cross-section, with ventral area slightly dorso-ventrally flattened. Typical adullt size is 65-100 mm TL (2.5-4 in), with a maximum of about 125mm (5 in).
Forked tail. Single dorsal fin with 8 rays and no spines. Pelvic fins abdominal. No adipose fin. Anal fin with 6-7 rays, no spines.
Distinguishing Characteristics
Inferior mouth with fleshy lips and no barbels. Dark lateral stripe on body. 8 dorsal rays. 43-51 lateral line scales. About 34 scale rows around body. See also similar species information.
Breeding Adults
Males have small tubercles on head, anterior body, and fins.
Similar to adults.
None known from Wisconsin.
Compare Similar Species
Chub, GravelSubterminal mouth; thin fleshy lips; no frenum
Chub, ShoalInferior mouth; thin fleshy lips; no frenum
Chub, SilverSubterminal mouth; thin fleshy lips; no frenum
Dace, Blacknose WesternSubterminal mouth; thick fleshy lips; frenum present
Dace, LongnoseInferior mouth; thick fleshy lips; frenum present
Minnow, SuckermouthInferior mouth; thick fleshy lips; no frenum
Stoneroller, CentralSubterminal mouth; ridge on lower jaw; no frenum
Stoneroller, LargescaleSubterminal mouth; ridge on lower jaw; no frenum
Sucker, WhiteInferior mouth; thick fleshy lips; no frenum
Chub, GravelInconspicuous
Chub, ShoalShort but conspicuous
Chub, SilverInconspicuous
Dace, Blacknose WesternInconspicuous
Dace, LongnoseInconspicuous
Minnow, SuckermouthNone
Stoneroller, CentralNone
Stoneroller, LargescaleNone
Sucker, WhiteNone
Body Pattern
Chub, GravelX, W, & Y markings
Chub, ShoalPepper-like spots
Chub, SilverSolid silver
Dace, Blacknose WesternMottled and/or lateral stripe
Dace, LongnoseMottled and/or lateral strip
Minnow, SuckermouthLateral stripe (may be faint)
Stoneroller, CentralMottled and/or lateral stripe
Stoneroller, LargescaleMottled and/or lateral stripe
Sucker, WhiteSolid, spotted, or mottled
Lateral Line Scales
Chub, Gravel38-43
Chub, Shoal36-40
Chub, Silver37-47
Dace, Blacknose Western60-75
Dace, Longnose61-75
Minnow, Suckermouth43-51
Stoneroller, Central47-58
Stoneroller, Largescale41-48
Sucker, White39-115
Circumferential Scales
Chub, Gravel~ 32
Chub, Shoal~ 28
Chub, Silver~ 28
Dace, Blacknose Western~ 52
Dace, Longnose~ 54
Minnow, Suckermouth~ 34
Stoneroller, Central38-50
Stoneroller, Largescale29-38
Sucker, White~32-~90
Dorsal Rays
Chub, Gravel8
Chub, Shoal8
Chub, Silver8
Dace, Blacknose Western8
Dace, Longnose8
Minnow, Suckermouth8
Stoneroller, Central8
Stoneroller, Largescale8
Sucker, White9-15
Similarity Index
Chub, GravelModerately similar
Chub, ShoalModerately similar
Chub, SilverModerately similar
Dace, Blacknose WesternModerately similar
Dace, LongnoseModerately similar
Minnow, SuckermouthN/A
Stoneroller, CentralModerately similar
Stoneroller, LargescaleModerately similar
Sucker, WhiteModerately similar
Sucker, WhiteAll suckers at the juvenile stage (Catostomidae: Catostomus, Hypentelium, Minytrema, Moxostoma) are moderately similar and all criteria as described for the white sucker apply.