If you're talking about the Yellow "tree" monitor, or V.Melinus, It is deffinatly not in the same family as Macraei. Yellow Tree Monitor is a really bad name for these, as they fit in more with the Indicus family than anything. Look at one, the tail, body, head is nothing like any member of the "tree" family (Prasinus, Beccari, Macraei, Bohemi etc.). While you never really know, I would think that there would be no way to cross these species as they are so different. The Melinus would probably get quite a bit larger than the Macraei. Before I would by anything from anyone, I would do a search of the BOI (Board of Inquiry) to see if there is any info on the seller. I would just wait and save till I could afford a Macraei female and keep the species pure as there is really no one having any luck with these in this country. Hope it helps. -Jeff