SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '554af62ab65aa792dad1ea28f23a679e4c43ec170e4b29f58f7d48820a27bad9' 
  AND token = 'awuTZPwgwePmRa+5dkt18Iez9E/I4oTJSK5u60ufzUU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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