For the record, determining whether or not a Pokemon is based on the same "species" is really really debatable, especially since most Pokemon aren't that specific about their origins. The two I can think of off the top of my head that ARE based on specific species are Caterpie, who is based specifically on swallowtail butterfly larvae, and Beautifly, who is based specifically on a swallowtail butterfly (I wonder why no one has made a theory out of that? Oh well). But the rest of their individual lines are very vague about their exact "species". And that's only ONE example, there are plenty others, where Pokemon totally change species between evolutions.
I assumed you were using "species" in the context of "fish" or "dog" or "cat" or "bird" and the like. But since you aren't Mamambou and Luvdisc really aren't the same species, they just have a similarity that Gamefreak caught on to. Luvdisc is a discus fish and Mamabou is a mambo/sunfish.
Hell, I might not even be using "species" right. "Genus" is probably more what we're looking for.
I assumed you were using "species" in the context of "fish" or "dog" or "cat" or "bird" and the like. But since you aren't Mamambou and Luvdisc really aren't the same species, they just have a similarity that Gamefreak caught on to. Luvdisc is a discus fish and Mamabou is a mambo/sunfish.
Hell, I might not even be using "species" right. "Genus" is probably more what we're looking for.