[pvaldes]

1) There are species of small "catfishes" (on Asia or Australia if I remember correctly) known to climb waterfalls in rainforests. We are talking about > 100m long fully vertical waterfalls.

2) In fact, they aren't catfishes. Belong to a big family of mainly marine fishes called gobies. Totally different orders. Should be named climbing gobies.

3) They do it for the same reason as Salmons do: to reproduce in freshwater.

4) But unlike salmons they don't swim or jump. They climb the slippery rock wall like a freestyle climber, using the suction cups in their belly that gobies have (pelvic fins transformed), and their other fins and tail to propel

5) Somebody filmed those fishes climbing.

[SideburnsOfDoom]

The article says "Rochedo, Brazil" so South American rainforests, in this case.

These species are "restricted to fresh water in South America" source: https://en.wikipedia.org/wiki/Pseudopimelodidae#Distribution

[pvaldes]

Hum, yep. You are right, Pseudopimelodidae are catfishes. I was thinking in the Hawaiian climbing goby.