A promegakaryocyte is a precursor cell for a megakaryocyte, arising from a megakaryoblast.
The developmental stages of the megakaryocyte are: CFU-Me (pluripotential hemopoietic stem cell or hemocytoblast) → megakaryoblast → promegakaryocyte → megakaryocyte.
Micromegakarioblast and Micromegakariocyte seen on MDS(Myelodysplastic Syndromes).