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Re: PROBLEM WITH AMPHIBIAN GILLS



darren.naish@port.ac.uk wrote:
>
> 
> It is artistic convention to reconstruct certain Palaeozoic - early
> Mesozoic amphibians with bushy or branched external gills, like those
> seen in extant neotenous caudates and most lisamphibian larvae. Is
> this idea based on nothing more than the idea that, because extant
> aquatic lisamphibians sometimes have external bushy gills, ancient
> fossil ones did too? Or is there some proper evidence? I am aware
> that branchiosaurs and various other fossil larval amphibians really
> do have bushy external gills (they can often be seen in
> well-preserved individuals), but what about all these pictures of
> bushy-gilled plagiosaurs, _Ophiderpeton_ and so on?

I totally agree, there is not reason, nor is there any REASON to have
thier skin smooth like modern amphibians. They had scales.
> 
> If there is no good evidence for bushy external gills in these fossil
> taxa, I am wondering if they should be removed. Extant
> _Megalobatrachus_, which is virtually entirely aquatic and can reach
> 1.5 m and more, has no external gills thus big aquatic lisamphibians
> do not need them.

I think it's the 'term' amphibian that throws people off.  They should
be called amnoites (as Rober Carroll once corrected me), and only the
lisamphibians should be called amphibians. 

Tracy