Hung's Chattering Fish
https://web.archive.org/web/20111005081 ... ngFish.pdf
https://i.pinimg.com/originals/59/4d/40 ... 0ed199.jpg

or this
Viet's Piranha
https://www.giladorigami.com/origami-da ... ier%20Viet
(which looks very similar)
I successfully folded Junior Jacquet's "kissing fish" (numerous examples on the internet), but I really don't understand the directions for Hung's Chattering fish. I am especially confused by the directions in steps 5 and 6.