Apateon

Full Name:  Apateon pedestris

Name Meaning:  Deceiver with Legs

Geologic Era:  Late Carboniferous to Early Permian

Location Found:  Pfalz, Germany

Estimated Range:  Europe

Size:  Up to 12 cm long

Extinction Date:  290 million years ago

This fossil is a beautiful example of a full body impression.  One can easily see the vertebral column, as well as the bone of the skull.  Also outlined is the body of the whole amphibian, including impressions of the limbs.  This fossil may be small, but it gives a rare insight into the body of an extinct amphibian.  Superficially, Apateon looked much like a modern newt.  

The dark blotch on the lower left corner is not natural to the stone matrix.  Thor, one of my greyhounds, was VERY interested in this piece of rock, and nearly mistook it for the most expensive dog treat he has ever had.  Luckily, a lick or two convinced Thor that while little Apateon may have been a nice snack 300 million years ago, it was a bit past the expiration date.  

Apateon’s skeleton appears to have been mostly cartilage, with only portions of the skull and vertebral column being ossified.  Apateon had no holes in its skull (aside from the orbital openings) and so would have had an extremely weak bite.  It could, however, open its mouth very wide for its body size.  It is probably that Apateon was a filter feeder.  This means that it would have gotten its food by leaving its mouth open and allowing food particles and organisms to flow in.  

This implies that Apateon lived in flowing water such as streams and rivers.  It is unlikely that an animal as small as Apateon could have swum against a strong river current, so it probably sat on the bottom, but close enough to the surface to breath.  The tail is also proportionally very long compared to the rest of the body.

Apateon helped to revolutionize the family tree of temnospondyls.  Temnospondyls are an extinct branch of amphibians, but one of the first types animals that could function equally well in land or water.  When fossils of Apateon were first found, it was assumed that they were larval forms of larger, more well known temnospondyls.  A closer examination revealed that the specimens were adults, or at least were capable of neoteny.  

Neoteny is when an animal is sexually mature even in its larval stage.  This is an advantageous trait in that an animal can reproduce quickly, increasing the likelihood of passing down its genes.  While this may have been a beneficial trait for Apateon, it did not help them survive to the modern day.  However, Apateon may have survived indirectly.  Temnospondyls are now widely considered to be the ancestors of lissamphibians, under which all modern amphibians fall.  

Image Credits:

Life Restoration: http://dinosauri-bakov.blog.cz/galerie/praveka-zvirata/obrazek/37903298