Many fossils of the long-tailed pterosaur Rhamphorhynchushave been found in marine deposits - so much that it has been theorised to be primarily aquatic - like a grebe or a cormorant.
I took the “aquatic rhamphorhynchoid” idea to its logical conclusion and illustrated Ichthyopteryx sp. a fully-aquatic descendant of this lineage. It looks quite plausible; I can picture heaps of them flopping about on beaches of remote islands. I wonder which lengths this line of evolution would extend to - if it was real. Just to clarify, this is not a real animal, but the product of an exercise in speculative-evolution.
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