The coelacanth left no fossils, so far as is known, since those fossilized “hundreds of thousands of years ago” as commonly stated, and yet live in the ocean today. The lack of evidence of them in between is not evidence that they didn’t live through all those years (as claimed for the marine reptiles in the article) only that they have not been found among the fossils of those layers. Obviously individuals lived and died and their descendants are alive today.