White-spotted cat snake 
Whitetail Lancehead 
Wiegmanns striped gecko 
Williams Dwarf gecko, Electric Blue Gecko 
Woma Python 
Wrights skink 
Yacare caiman 
Yanez's lava lizard 
Yarará Lancehead 
Yarrows spiny lizard 
Yellow anaconda 
Yellow Bellied Slider 
Yellow-bellied sea snake 
Yellow-bellied Water Skink 
Yellow-blotched Palm Pit Viper 
Yellow-collared Wolf Snake 
Yellow-faced whipsnake 
Yellow-footed tortoise 
Yellow-green Cat Snake 
Yellow-headed gecko 
Yellow-headed water monitor 
Yellow-lipped sea krait 
Yellow-spotted Amazon River Turtle 
Yellow-spotted night lizard