How to Identify Longnose Sucker

To identify Longnose Sucker (Catostomus catostomus), look at these key features.

Physical Characteristics

Body shape

elongated

Coloration

Dorsal surface typically dark olive to black, fading to lighter olive or silvery-white on the flanks and belly. During spawning, males may develop a reddish lateral stripe and nuptial tubercles.

Scale type

cycloid

Mouth position

inferior

Distinctive features

Long, conical snout projecting significantly beyond the mouth., Ventral, protractile mouth with thick, papillose lips., Large, cycloid scales., Lateral line complete, with 90-120 scales., No barbels.

Dorsal fin

Single dorsal fin, typically with 10-13 rays, located mid-body.

Tail fin

Deeply forked caudal fin.

Pectoral fin

Moderately sized, located low on the body.

Distinctive fins

Pelvic fins are abdominal, located well behind the pectoral fins.

Identification Tips

1. 1

   Snout

   The most distinguishing feature is the long, pointed snout that extends noticeably beyond the mouth. This is key to differentiating it from other suckers.

2. 2

   Mouth

   The mouth is ventral (on the underside of the head) and protractile, with thick, fleshy, papillose lips adapted for scraping and sucking food from substrates.

3. 3

   Lateral Line Scales

   Count the scales along the lateral line; Longnose Suckers typically have 90-120 scales, which is higher than many other sucker species.

4. 4

   Coloration

   Observe the overall body color, which is usually dark on top and lighter below. Spawning males will exhibit a distinct reddish lateral band.

Explore Longnose Sucker