It turned out that there are two species, both of which occur in West Africa and historically also occurred in the Nile (ancient Egyptian sources already distinguish between the two species).
Caution is always advised when it comes to genetic studies that postulate new species. Usually only parts of the genome are examined and only of parts of the population; it remains unclear whether the genetic differences have any effect at all or merely concern junk DNA; there is no clear boundary as to how much genetic difference constitutes a new species, so the researchers concerned decide arbitrarily whether they feel like describing a new species.
But here we also have sympatric occurrence, so it is quite clear that there are two species.
@captain alligator That's what geneticists say, but without any solid argument. Genetic differences within a population are normal in every population. There is no argument why in this case this should be enough for different species.
Especially in the case of the Slender-snouted crocodile: Two populations of one species have simply been turned into two species of a new/reerrected genus.
What used to be the species is now simply the genus.
