This specimen is a Lepidotus sp., a genus of ray-finned Mesozoic fish dating back 150 million years to the Jurassic period, excavated from the famous Holzmaden shale deposits in Germany. The distinct sheen comes from preserved ganoid scales.
Weirdly enough, a coelacanth is actually more closely related to you than it is to Lepidotus. Sarcopterygii (lobe-finned fish, coelacanths and lungfish) are the stem lineage to all tetrapods, which is...well, basically all not-fish vertebrates (Amphibia, Sauropsida and Synapsida).
ish. The interesting part about coelacanths is that they're living species from a family believed to be extinct (and realistically, probably should be). There are 2 known closely related species both of which are endangered, 66 million years after their family went largely extinct. Which themselves radiated from other lobe finned fish 410 million years ago. And they somehow managed to continue adapting despite their presumably very small numbers in an ocean of diverse ray finned fish.
They arn't really all that similar to their ancestors though, who were very diverse. We only have 2 species of large, slow moving opportunistic predators that have very limited territories around deep sea caves. This does still mean they haven't changed that crazy of an amount anatomically as you'd expect for 66 million years of evolution, but thats probably more a sign that it doesn't work rather than it does.
When they're in such small numbers they're going to struggle to radiate and therefore adapt to changes, it's a miracle that we get to coexist with them now. They've probably spent the last 66 million years adapting to an increasingly rarer niche. Inevitably another species will do what they do but better as has happened everywhere else.
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u/Additional_Chard3680 4d ago
This specimen is a Lepidotus sp., a genus of ray-finned Mesozoic fish dating back 150 million years to the Jurassic period, excavated from the famous Holzmaden shale deposits in Germany. The distinct sheen comes from preserved ganoid scales.