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Re: Practical work experience?

We will present just a small and crushed nucleotide, and a small part of
protein (type of collagen) preserved in the fossil of Discosauriscus. We
tested it and showed that it is not contamination


We call it ''amphibian'' because the congress is not on Palaeontology, but
on Aminoacids and Proteins, thats why we wanted it to be more clear

That's what I'm saying: to call it an amphibian is misleading, because the real amphibians are more closely related to us than to *Discosauriscus*. Unlike much of nomenclature, this not an academic word game -- it has practical implications: it means, for example, that the collagen of *Discosauriscus* should be less similar to those of amphibians than ours is.

And by the way I would like to comment on previous question about
electroreceptors in primitive tetrapoda

Discosauriscus had elecroreceptors.

Based on your biochemical research?

The fact that Discosauriscus had electroreceptors is not by our research,
but by the anatomical research made by Klembara J. (1997)

Ah. That's not it, but it cites the following paper which does make an argument in this direction:

J[ozef] Klembara (1994): Electroreceptors in the Lower Permian tetrapod *Discosauriscus austriacus*, Palaeontology 37(3), 609 -- 626

Klembara notes that the "foraminated pits" in the skull of *D.* also occur in many other aquatic vertebrates and have been compared to the ampullae of Lorenzini (electroreceptors of cartilaginous fishes) and the "bottle-shaped organs" of lungfishes. Then (p. 623) he offers the following:

"As well as in fishes, ampullary organs have also been found in representatives of two groups of extant tetrapods: the caecilian *Ichthyophis* [...] and the urodeles *Triturus*, *Salamandra* and *Ambystoma* [...]. However, as in extant fishes, the ampullary organs of urodeles do not leave traces in the external surface of the dermal cranial bones. [...] the ampullary organ [...] is more or less recessed below the epidermis [...] and connected to the surface by a canal [...]. During the terrestrial phases of the urodele's life, the canal of the ampullary organ is closed by the outer epidermal layer."

So electroreception is the normal condition for tetrapods, and lost in terrestrial life stages and clades! Thank you for having pointed me at Klembara's work. :-)