Spermatophoren

Spermatophoren, also known as spermatophores, are reproductive structures that carry and deliver sperm from male to female in a variety of animal groups. They are typically produced by specialized reproductive glands and may consist of a spermatozoa-containing core enclosed in a protective envelope. In some species the spermatophore also contains nutrients or other substances that can influence fertilization or female physiology.

Formation and structure can vary widely. Some spermatophores are deposited in the environment or onto the female’s body and later taken up, while others are delivered directly during mating. In cephalopods such as octopuses, males use a specialized arm to insert enlarged spermatophores into the female’s mantle cavity or reproductive opening. In many mollusks and crustaceans, spermatophores are transferred in a more external manner, with the female storing or using them for fertilization later. In terrestrial gastropods (land snails) and other hermaphroditic species, individuals often exchange spermatophores during mating.

Function and significance also vary. Spermatophores can protect sperm from desiccation, predation, or microbial attack, and may extend the window for fertilization. They can also carry substances that influence female allocation of resources to offspring or mating behavior. The production of spermatophores reflects diverse reproductive strategies across taxa, including direct insemination, external deposition, and exchange between partners, illustrating how sperm transfer has evolved in different ecological contexts.