The giant bill of the chestnut -
mandibled toucan makes up a third of the bird's body length, but thanks to a honeycomb structure, it's not as heavy as it looks.
Keel - billed Ramphastos sulfuratus and chesnut -
mandibled toucans Rampahstos swainsonii are the largest (18 inches and 22 inches respectively), black with bright yellow «bibs» and multihued bills.