Morphology and ultrastructure of the earthworm Dendrobaena veneta (Lumbricidae) coelomocytes.

Microscope techniques, light microscope (LM), transmission electron microscope (TEM), scanning electron microscope (SEM) were employed to describe and classify coelomocytes of the oligochaete Dendrobaena veneta. Three main cell types were distinguished in the coelomic fluid: eleocytes, amoebocytes and granulocytes. Eleocytes are large, oval cells containing characteristic granules called chloragosomes. Amoebocytes are most numerous coelomocytes and have been divided into two types (I and II). Both amoebocytes of the types I and II often form aggregations of a few to about a dozen cells. Granulocytes are oval cells with spherical nuclei and cytoplasm containing polymorphic, electron dense granules. Contrary to the amoebocytes, the granulocytes do not form aggregations. Morphology and ultrastructure of coelomocytes are presented on micrographs: similarities and differences are compared to coelomocytes of related species.