Sunshine and a cooperative little shorthead.
Is there a word or term for that zone of both rays and barely-formed scales, or for the stage of scale formation where they are more hints than scales? If not, there ought to be. Suggestions?
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Channel catfish (Ictalurus punctatus) small enough to be translucent. Kankakee River, Aroma Park, IL, 9-23-2013
This little channel catfish (8 or 9 inches at most) also had a healthy glow when x-rayed by the sun.
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The flexible part of the caudal peduncle (the intermediate zone that you refer to) is referred to by ichthyologists as the “caudal base.”
Thanks. I knew that term, but for some reason didn’t think of it as I wrote this post. I’m still curious about the terminology of scale formation. I just need to remember to do some searching when I have some free time.