FURTHER OBSERVATIONS ON THE ULTRASTRUCTURE OF MATURE SPERM OF SCUTIGERA-COLEOPTRATA (L) (CHILOPODA, SCUTIGEROMORPHA)

Mature sperm of Scutigera coleoptrata, taken from the spermatheca, were investigated by scanning (SEM) and transmission (TEM) electron microscopy. The only sperm type observed was of enormous length, the head measured about 500-mu-m and the tail up to 3.5 mm. The acrosome, the smallest found in Chilopoda sperm (0.25-mu-m), showed a bilayered arrangement, described here for the first time. The tail exhibited the typical 9 + 2 microtubular pattern surrounded by a striated cylinder and four mitochondrial derivatives. These were anchored to the striated cylinder by peculiar mitochondrial bridges. The end-piece, never previously described in Scutigeromorpha, showed a small 'plume' under TEM.