What is a young, anucleate erythrocyte called?

The right answer is reticulocyte.

The reticulocyte is the cell preceding the erythrocyte stage in erythropoiesis. He is almost like her.

Reticulocytes are young red blood cells that still have ribosomes and mitochondria, but no peroxisomes. They are therefore capable of a fairly intense metabolism and they still actively synthesize hemoglobin.