SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '218885f43e08765e8331017b4d81571bd3146c7704e54ddacef6e7c01b079087' 
  AND token = 'EYHJw67i/a6dPeqjzBki67AVSjUug4reBJWpUzfniw0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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