develops from embryonic/larval hemocyte prohemocyte embryonic hemocyte primordium embryonic/larval head mesoderm derived hemocyte fly_anatomy.ontology Hemocyte of the embryo or the larva that is derived from the head mesoderm of the embryo. These hemocytes populate the embryo and continue to replicate throughout larval stages with some persisting in pupa and adults. head mesoderm derived embryonic haemocyte FBbt:00005916 head mesoderm derived embryonic hemocyte head mesoderm derivative