Four digits on the Forelimb

Image of a modern newts fore limb showing 4 digits

The picture shows the forelimb of a modern newt. You can clearly see that it only has 4 digits. The same is correct for the temnospondyls. The newts are part of the Lissamphibia which are related to the temnospondyls as neither group are amniotes yet still tetrapods.In some of the pictures on this site you may notice that the forelimbs actually show 5 digits. Even some of the skeletons have had the 5'th digit added on in the lab despite there not being one found. These are common mistakes and experts are all now in agreement that the temnospondyls had 4 digits ,except for very few cases where one specimen turned up with 5 digits. This is probably due to a random mutation, similar to those seen in humans with 6 fingers.

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