can someone please explain to me what the "L" in some plecos' names mean
like I can kind of understand some plecos being line bred like blue phantoms
and I guess the L in that is the line
is that what it is? line? line number? generation of development?
L# = loracarid number. Its just an alternate naming system for plecos since many don't have scientific names. That being said not all plecos have an L number but most in the hobby do, generally new types of plecos get an L#. For instance, zebra plecos are L46. It eliminates ambiguity since "royal pleco" could mean several different types of pleco like L191, L27, etc, and the scientific nomenclature isnt completely hashed out. Has nothing to do with beng line bred. (also blue phantoms are not line bred, they are actually a rather difficult pleco to breed... most in the hobby are wild caught to my understanding). I think you're conflating L numbers with F numbers (F1 = first generation offspring, F2 = second generation and so on).