It is my understanding that Dr Thomas is at the New York Botanical Garden, and is considered to be something of an expert on the Brazilian Atlantic Coastal Rain Forest. I thought perhaps some of the plants you have trouble finding an identity for may be included in some of his work. Possibly he has on-line reference information.
Every time I get a few minutes to spare I have been looking for matches for your tree. I thought a picture I ran across looked similar but it was a cocoa tree flower..
