Lake Chubsucker
  • 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 of head: The mouth is terminal.
  • The body depth is more than 30% of SL; there are usually 35-37 lateral scales and a posteriorly placed anal fin.
  • Close-up of mouth/snout: The lower lip is fleshy.
  • Close-up of dorsal fin: There are usually 11-12 dorsal rays.
  • Close-up of flank: Notice the absence of pored lateral line scales.
  • Close-up anal fin of a breeder: The anal fin is sickle-shaped with many smaller tubercles.
  • Side view of a breeder: The head shows 3 large tubercles, the anal fin is sickle-shaped with many smaller tubercles.
  • Close-up head of a breeder: Notice the 3 large tubercles on the snout.
  • Side view of young-of-year: They are similar to adults except for their more pronounced lateral stripe.
  • Alternate top view showing "saddles" on the back which are partially confluent with blotches on the sides.
  • Alternate side view of an adult.
DescriptionSimilar Species
Suckers (Catostomidae)
Mouth and snout: subterminal, no teeth on jaws. No barbels. Body patterning, color, and scales: Single lateral stripe, solid color, or 5-8 faint lateral blotches. Body overall olive, dark tan, or gray above lateral area grading to cream on the belly. Fins without distinctive markings and limited dark pigment. 33-40 (usually 35-37) cycloid lateral line scales; none with pores (lateral line absent). Body shape and size: Body fusiform to somewhat laterally compresse and moderately deep in adults; oval in cross section. Typically 150-250 mm (6-10 in) TL; maximum in Wisconsin about 300 mm (12 in).
Tail, dorsal and other fins: Forked tail. Single dorsal with no spines and 10-13 (usually 11-12 rays). Pelvic fins abdominal. Adipose fin absent. Anal fin usually with 7 rays.
Distinguishing Characteristics
The lake chubsucker can be distinguished by its lack of a lateral line, its more posteriorly placed anal fin (distance from front of anal fin to caudal base contained more than 2.5 times in the distance from the front of the anal fin to the tip of the snout), its 9 or more (rarely 8) dorsal rays, by its thick fleshy lower lip, by its lack of an exposed cartilaginous ridge on the lower jaw, and by its subterminal mouth position. See also similar species information.
Breeding Adults
Males with three large tubercles on each side of snout and numerous smaller tubercles on anal fin; anal fin sickle-shaped; yellow fins; and blue-gray head.
Less deep bodied with more pronounced markings (lateral stripe or blotches).
Compare Similar Species
Dorsal Fin Rays
Chubsucker, Creek8-11, usually 9-10
Chubsucker, Lake10-13, usually 11-12
Lateral Scales
Chubsucker, Creek37-45, usually 39-41
Chubsucker, Lake33-40, usually 35-37
Body Depth (% of Standard Length)
Chubsucker, Creek24-31%, usually <30%
Chubsucker, Lake29-35%, usually 32-34%
Similarity Index
Chubsucker, CreekVery similar
Chubsucker, LakeN/A