Wildflowers: Yellow flower

Hi
I found the flower growing on Mt Uluguru in Tanzania.

 

Having no luck with this one. Closest I came, and I'm 90% certain I'm off, is Cassia afrofistula. Frustrating thing is I'm fairly certain I've seen this before.

Can you give a few more details? Is it definitely native? Tree? Shrub? Description of leaves?

Those stigmas are very distinctive.

 

Yes it is native. It was growing on the mountain, in the wild.

I dont have leaves, but I think it was a shrub, bush like. Thanks

 

How about:

Aneilema aequinoctiale via Aluka

Aneilema aequinoctiale via Dr. Gerald Carr's pages on plant families

 

Yup that's the one.

Thanks for the help

 

What an interesting flower! How big is it? Thumbnail sized?