Spermatophore formation and transfer in Arion lusitanicus Mabille, 1868 (Gastropoda: Pulmonata: Arionidae)

Spermatophore formation and transfer in slugs are complex and still obscure. In the slug Arion lusitanicus Mab. the spermatophore is formed 30–35 minutes after atrium eversion; as long as the copulating slugs are connected, each spermatophore is partly in the donor’s epiphallus and partly in the recipient’s spermatheca duct; spermatozoa are released in the spermatheca duct 12–13 hrs after the spermatophore transfer; the spermatophore tunicle in the spermatheca dissolves within 48–72 hrs.