On the spermatophore implantation in bobtail squid Rossia macrosoma(Cephalopoda: Mollusca)

In this study, mated female specimens of Rossia macrosoma from the Aegean Sea were examined. During mating, the male places spermatangia on the head of the female (typically around the eyes), and on the anterior mantle edge, particularly on the left side near the oviduct opening. To determine implantation structure type, deeply intradermal implanted spermatangia were dissected from mated females and their structures were investigated through histological analyses. Outline structure of the spermatangia consists of a spiral filament, sperm mass, cement body and a trailing end. The cement body is located centrally surrounded by the sperm mass from the view of the histological cross section. Spermatangia could be implanted in females' tissue autonomously by major role of the spiral filament located on the oral part of spermatangia. Implanted spermatangia have thin, capillary-tubule shaped trailing end located aborally. In our opinion these trailing end, transfer spermatozoa obtaining fertilization of the eggs in the external environment.