Butterfly logo Fauna

Every token
has a face.

Fauna is a fungible token. Every unit is also a butterfly with a permanent ID, rendered fully onchain.

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The Idea

Fungible tokens
are anonymous.
These aren't.

Send 10 USDC and you get back 10 USDC. There's no way to tell which 10 you got. Every unit is interchangeable and identity-free.

Fauna works differently. Every unit has a numeric ID. Ownership is tracked as sorted ranges on-chain, so the system handles millions of IDs without a storage slot per token. Transfer some FAUNA and specific IDs move with it.

The same token is also an ERC-721. You can look up any ID in a wallet, trade it on a marketplace, or transfer a precise range when it matters. No off-chain metadata, no IPFS. The art lives in the contract.

How It Works

Range Ownership Balances are stored as sorted intervals [start, end) → owner. A wallet holding 1 million units uses a handful of storage slots, not a million.
ERC-20 + ERC-721 The base contract is a standard fungible token. A mirror contract reads the same ownership and exposes it as ERC-721, so butterflies show up in wallets and on marketplaces.
Uniswap v4 Hook A custom hook keeps range ownership in sync after swaps and liquidity changes, so NFT identity stays aligned with fungible balance moves through the pool.
Onchain Art Millions of trait combinations. Species, rarity, palette, pattern, margin. Each butterfly is derived deterministically from its token ID and rendered as SVG on demand.