SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5feb8d75e419bd05af5b8a90afae96d6cc6fb3892136e7a1f782652fbddc8c36' 
  AND token = '9weeOM6PTZ2/5D8xWFFrbwDfXaDPtOR5BsNPMppuDBU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}