Adds beetles that you can grow from endermites by feeding them shulker shells. The beetles drop carapace and chitin. Carapace can be crafted with phantom membranes to make an Elytron, witch can be crafted with more carapace and membrane to make the Elytra. Carapace can be crafted into chitin and vice versa. Chitin can be made into biolith in a similar recipe to concrete. Biolith has mostly the same variants as stone/stone bricks.
post 1.18.2 biolith can no longer be crafted into bricks.