Races of the Source vs the First and those unique to each

[Brightamethyst]

I think too much of the 1st Shard has been destroyed to say if the races we don't see on the 1st Shard weren't actually there at some point in time. Other then races like the Ixal (which are Allagan creations) it's entirely possible they migrated to different parts of the 1st Shard and were simply swallowed up by the Flood.

Pretty much this. We only know what we see. There could very well be First versions of goblins, ananta, vanu vanu, etc, and we just don't know about it because they were all gone long before we ever got there.