| 1a) |
No spots (pale or dark) on back or flanks; base of anal fin longer than base of dorsal fin; 13-17 rays in anal fin
-> Kokanee, Oncorhynchus nerka
|
| 1b) |
Spots (pale or dark) on back and flanks; base of anal fin shorter than base
of dorsal fin; 8-12 rays in anal fin
-> see 2a |
| |
|
| 2a) |
Spots on back and flanks dark against a light green or light brown background; well developed teeth on shaft of vomer (Fig. A)
-> Rainbow trout, Oncorhynchus mykiss |
| 2b) |
Spots on back and flanks light (cream, orange, or red) on a dark background; no teeth on shaft of vomer (Fig. B)
-> see 3a |
| |
Figure A |
Figure B |
|
| 3a) |
Dorsal fin heavily marbled with dark wavy lines; some spots on lower flank with bluish haloes
-> Brook trout, Salvelinus fontinalis |
| 3b) |
Dorsal fin dusky or lightly spotted, not heavily marbled (i.e., no with dark wavy lines); spots on lower flank without bluish haloes
-> see 4a |
| |
|
| 4a) |
Irregularly shaped pale spots on the back, sides, dorsal and caudal fins. The spots are grey or whitish (never coloured) and the tail is deeply forked (the centre caudal rays are about half the length of the longest outer rays)
-> Lake trout, Salvelinus namaycush |
| 4b) |
Light regularly shaped, spots (often coloured) on the sides. No spots on dorsal or caudal fin. Tail almost square, (the centre caudal rays are almost as long as the longest outer rays
-> see 5a |
| |
|
| 5a) |
In profile, the snout is blunt (Fig. C); total number of branchiostegal rays usually less than 23; anal fin base almost equal to upper jaw length --- average ratio is 1.2 (range of 0.9-1.5)
-> Dolly varden, Salvelinus malma |
| 5b) |
In profile, the snout is pointed (Fig. D); total number of branchiostegal rays more than 23; anal fin base less than upper jaw length --- average ratio is 1.7 (range of 1.5-2.3)
-> Bull trout, Salvelinus confluentus
|
