SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '99ed6c320a42d2270b9a1ddc1be8bdc1750fc87be4c4873e6c517efbad48b0ef' 
  AND token = 'gvJS4zX8G4e0bWNwaeatdAQnUnmhkRDnJlR5ul1C7k8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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