One of these rows is the 6-decimal ERC-20 face of a movement that is also in this receipt as an 18-decimal Transfer from the native USDC mirror contract. It is one movement described twice, at two scales — not two movements.
A transaction is a cryptographically signed instruction that changes the state of the chain. Arc commits transactions under Malachite BFT consensus: once a block carries more than two thirds of the validator set's precommits it is final, permanently, and there is no confirmation window to wait out.
Unrecognised method 0xd3aeb009
No published ABI and no signature directory entry names this selector, so the payload is shown exactly as it was sent. Verifying the contract's source would name it permanently.
The decoder's reason: unknown function selector