IT APPEARS TO BE WHAT WE USED TO CALL DIEFFENBACHIA MACULATA VAR. ANGUSTIFOLIA.
GREEN STRAP LEAVES SPECKLED WITH WHITE SPOTS. IT WORKS MOST EXCELLENTLY IN THE INTERIOR SETTING ALMOST LIKE AN AGLAONEMA. BUT IT IS EXTREMELY SLOW GROWING BECAUSE THE LEAF BLADE IS SO NARROW THAT IT DOES NOT FILL THE POT UP WITH 6-8 LEAVES AND HAS TO SUCKER OUT AND FILL UP POT.
IT WAS USED TO MAKE HYBRIDS WITH OTHER D. MACULATA CULTIVARS BY Dr. Jake Henny at the University of Florida, but he had to double chromasomes to make a fertile back cross to F2 level.
As a result we have Dieffenbachia 'Starbright' which is being commercially produced as a tropical foliage plant for interior usage. Still a little slow, but an excellent house plant.
While picking up some plant donations from someone I noticed an unusual Dieffenbachia sp in their collection, and they let me have a piece. All this person knew was that it was wild collected, but beyond that he didn't have any info as to where it originated from. Any help with identification would be much appreciated. Here are some photos: