well frogprince,-assuming I get the import of your question!
firstly, I am not so sure that the examples of stasis are that isolated.
I am aware that darwinists will claim that if something hasn't changed over deep time till today, then it did not need to ,to survive.
assuming that is the correct understanding, then either that stasis survived through many changes in environment ,or it did change and woumd up the same again.
I presume the 2nd is not in the frame ,but it seems to me that positing no change in the organism while selective pressures kept changing seems very unlikely, but might well be entertained and embraced due to philosophical bias.
I am open to any [constructive.and of substance] deficiencies in my reasoning should that be the case.