It is reproductively isolated from other species of the genus Capsicum.

In other words, the group is reproductively isolated from other groups.

The two species in each lake are reproductively isolated; neither mates with the other.

The fish home to a specific spawning area and are reproductively isolated.

It is not known whether the two populations are reproductively isolated.

Many of these populations live in sympatry, yet are reproductively isolated.

They would be a natural population which is reproductively isolated from other such groups.

Genetics of the two isolates indicate that they are reproductively isolated.

Despite their independent origins, these populations are probably interfertile and not reproductively isolated from one another.

However, the three are reproductively isolated in the wild, which would argue for treating them as species.