Alstonia species?- BSI Experimental garden; Itanagar, Arunachal Pradesh

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Alstonia venenata? (Asclepiadaceae)_RKC05_081110– 8 posts by 6 authors. Attachments (6)
Loc.: BSI Experimental garden; Itanagar, Arunachal Pradesh (ca 550m); Date: Feb. 2008.:

A venenata looks like the ones you will find in the link below, Hence I think this is not the plant, though I am not very sure.
Toptropicals

Surely not Alstonia venenata

Alstonia sebusi (Van Heurck & Müll.Arg.) Monach. ??

I too disagree with venenata