when people ask if the fish is sailfin or common, they mean is it a pardalis or a gibbi.going sail fin for my part, 9 spine dorsal count. that is about the only def between a sail fin and a common. At least that is my understanding. I have a common and a gibby. 10" and 14" and years old. They live for ever.
Be careful there 3 types of common plecos. A hypostomus plecostomus(common) has fewer ray count then a sailfin. A Pterygoplichthys pardalis(also a common) has the same as a sailfin. A Pterygoplichthys disjunctivus(the 3rd common pleco) is nearly the same as a Pterygoplichthys pardalisgoing sail fin for my part, 9 spine dorsal count. that is about the only def between a sail fin and a common. At least that is my understanding. I have a common and a gibby. 10" and 14" and years old. They live for ever.