"Crabs" and "Dragonfly" are each crafted from a piece of square paper
with careful work. No part of the peper is cut. Instead the thin legs
and wings are made by folding the paper into small parts. These models
are made with very thin and strong Japanese paper (Washi). The thickness
of a bundle of hundred pieces of this Washi is less than 1mm.
It takes a long time to fold these models. The "Crab," which is more complex, takes about three hours, and the "Dragonfly" takes about an hour.
Instructions for these models are written in "Very difficult origami works for experts" by Kunihiko Kasahara.(Japanese)