Refer to this portion of a dichotomous key for fish identification to answer the question.
3
1. (a) has a single dorsal fin → 5
(b) has a double dorsal fin 2
2. (a) one fin is spiny, the other is smooth
(b) one fin is not spiny or smooth 4
5. (a) has small fin on back near tail →6
(b) has no fin on back near tail →7
6. (a) has barbs near the mouth → catfish
(b) does not have barbs near the mouth
7. (a) tail is asymmetrical → 8
(b) tail is symmetrical 9
10. (a) scales are small → trout
(b) scales are large whitefish
10
what is the next step to complete to identify a fish that has a single dorsal fin and no fin on the back near the tail?