The differences between Panama redrump(Sericopelma Rubroni) and Mexican red rump(Brachypelma vagans)

[Bingyu]

Hey guys, does anyone know how to distinguish the differences between these two spiders?
I just saw one called the Mexican red rump(Brachypelma vagans) in the shop, but the size is quite different from as what I have seen of the Mexican red rump. But their looks are similar so I can't tell.

 

[kormath]

They're almost identical. only difference I know of is the carapace is solid black on the S. rubronitens but the vagans has a tan edge.

 

[Bingyu]

Thank you for telling me that. it's useful. As I know, Sericopelma Rubroni looks more massive than vagans.