SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9b665fd82536e101a5ce1ea8db5402487cfcefb2692e26fd393c2be506c08411' 
  AND token = 'nGmDCzNPmC4X3iRcMkLqgYmyKXd+/vlyKhZ3cpLIEPM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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