I've got two little fish in a aquarium shop, but I am not sure about it specie. It is similar to an Otocinclus. I've find very similar fish in my grandmother's farm, in south Brazil. The seller told me it was Otocinclus, but it clearly isn't.
I've made a video of them, it is in the link below:
https://www.youtube.com/watch?v=A1Ee-N1L3bE
Some images to help in the identification:
- In the right there is an Otocinclus
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