SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '29aeb9e6c79fa3078c059ec901d8cb127d145c5310ae1b5a8c9f49fb200169ce' 
  AND token = 'zDpPcJh2fL7YXIVmmfJL9CqsHSBhKtD5vJa8hZMHjGA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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