I found the following information about Coelacanths.
Coelacanth" W.W. Norton & Company, New York and London,
1991 ISBN 0-393-02956-5
Page 78, last paragraph:
"One point has to be emphasized; The living coelacanth is not a
living fossil in the very strict sense that members of the species L.
chaumnae itself have ever been found as a fossil. In fact, no other
species assignable to the Genus Latimeria has been found as a
fossil either. Latimeria and the Cretaceous fossil Genus
Macropoma are quite closely related, and we could possibly
include them in the same family. Beyond that, all fossil coelacanths
belong to the order Coelacanthini."
He goes on to say that a minority of zoologists would prefer to call
Coelacanthini, Actinistia.
Kevin Koenig