Nitripervalida that have both holes, but the thumb hole is shaped and smaller than usual Duoforaminis Nitri. Believed to be the chain between the evolution from Duoforaminis to Opertoforaminis.
Figuraforaminis
A good site for information on various critters!
Nitripervalida that have both holes, but the thumb hole is shaped and smaller than usual Duoforaminis Nitri. Believed to be the chain between the evolution from Duoforaminis to Opertoforaminis.