Spermatozoal phagocytosis by the spermathecae of Dendrobaena subrubicunda and other lumbricids (Oligochaeta, Annelida)

Spermatozoal phagocytosis by pseudopodial-like, avillous portions of the spermathecal epithelial cells of Dendrobaena subrubicunda is described at the ultrastructural level. The resultant phagosomes are digested by an aryl sulphatase-rich lysosomal system. Sperm ingestion also occurred in Allolobophora caliginosa, A. chlorotica, A. longa and Lumbricus rubellus. All specimens were collected in late autumn-early winter, and phagocytosis is discussed in relation to the removal of ageing and/or aberrant sperm during the months when cocoon-production is minimal. In the parthenogens A. rosea and Octolasion cyaneum and in the amphimictic Eisenia foetida, the spermathecal epithelium possessed a continuous microvillous brush border and the cytological features associated with phagocytosis were not observed. The apparently anomalous condition in E. foetida is discussed.