Purdiaea
"Purdiaea" is native to tropical regions of the Caribbean ( with the highest species diversity on Cuba ) , Central America and northern South America , further south than the related genus "Clethra" , the only other genus of this family . 
<triplet> Caribbean <subj> Central America <obj> continent <subj> South America <obj> continent <triplet> Central America <subj> Caribbean <obj> has part <triplet> South America <subj> Caribbean <obj> has part