Thanks for all the replies, people!
I realise id-ing these kinds of fish is quite a nightmare...
After looking at the pics suggested more closely, I'd say it does resemble
L133 more closely than
Baryancistrus cf. niveatus.
The spots on my fish are larger than the Baryancistrus, but then, I don't know the size of that fish, nor how large the spots grow once they get larger...
But in general appearance, it resembles Scobinancistrus more closely, imo. - the (caudal and dorsal) are as dark as in the planetcatfish picture, with no fin rays visible (as in most Baryancistrus pics). No idea how much value this has, though.
I haven't had the opportunity to have a closer look at the mouth/teeth, since it usually hangs out in the back of the tank - God knows what it's up to at night, though...
I'll see if I can get some better shots.
Anyways: thanks for the suggestions, and if any of you have other pointers/suggestions, please, let me know
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