"common pleco" species

from what i can tell the most likely species i have is Pterygoplichthys pardalis

not 100% sure yet though.
 
If your fin-ray counts are correct then a species of Pterygoplichthys is most likely.

In the UK, 20 years ago "H. plecostomus" (hard to be sure of the exact species with no info on collection location for the original fish before they were shipped out to the Far East) was by far the most common plec offered for sale, but P. pardalis now seems to be by far the most common.
 
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