You: An interesting and very good point.
Explain please! I posted 1208 to you yesterday.
See, this is Creation Science 101. No facts, no logic. Just blithely ignore all refutations and keep pretending that pasture pie is filet mignon.
I'm trying to avoid being a lawyer with words -- i.e. allowing "species" a very broad definition -- but most of the classes of plants and animals of which there are fossils exists today.
Go back to your link in post 1208. How many classes are extinct? Are we confident in our taxonomy? Are we going to call something a class today that we were calling a subphylum yesterday?
And what exactly was a trilobite anyway? Maybe it is more closely related to the horseshoe crab than we believe. Taxonomy by fossil is pretty speculative.
A further note, one should avoid being definitive concerning the extinction of marine creatures. Consider the coelacanth.