How to Identify Round Whitefish

To identify Round Whitefish (Prosopium cylindraceum), look at these key features.

Physical Characteristics

Body shape

elongated

Coloration

Dorsal surface typically dark olive to brownish, fading to silvery sides and a white belly. Fins are generally dusky, sometimes with a reddish tint during spawning. No distinct spots or markings on the body.

Scale type

cycloid

Mouth position

subterminal

Distinctive features

Cylindrical, 'round' body shape (less compressed than other whitefish), Small, subterminal mouth (mouth opens slightly downwards, not reaching the anterior margin of the eye), Adipose fin present (a small, fleshy fin between the dorsal and caudal fins, characteristic of salmonids), Large, cycloid scales, Absence of teeth on the tongue

Dorsal fin

Single dorsal fin, relatively high, with 10-14 rays. Adipose fin present.

Tail fin

Moderately forked caudal fin.

Pectoral fin

Pectoral fins are relatively long and pointed.

Distinctive fins

Pelvic fins are abdominal, located well behind the pectoral fins. Anal fin has 9-12 rays.

Identification Tips

1. 1

   Body Shape

   Look for a distinctly cylindrical, 'round' body, unlike the more compressed bodies of other whitefish species like Lake Whitefish.

2. 2

   Mouth Position

   Observe the small, subterminal mouth that does not extend past the front of the eye. This distinguishes it from species with larger, terminal mouths.

3. 3

   Adipose Fin

   Confirm the presence of a small, fleshy adipose fin between the dorsal and caudal fins, a key characteristic of salmonids.

4. 4

   Coloration

   Note the generally uniform dark olive to brownish back, silvery sides, and white belly, lacking prominent spots or patterns.

5. 5

   Scales

   The scales are relatively large and smooth (cycloid), which can be felt by running a finger against the grain.

Explore Round Whitefish