Epigyne
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An epigyne ( ancient Greek ἐπί epi "on, on" and γυνή gynē "woman") is the external female sexual organ (copulatory organ) in entelegynous real spiders . It consists of the sclerotized parts, a cover and an insertion opening for the vulva and sits on the ventral side ( ventral ) of the abdomen ( opisthosoma ). Only the male secondary sexual organ, the embolus on the pedipalp of the same species, fits like a key into this lock . This could serve to prevent hybridization ; however, behavior-level inhibition mechanisms also play a role.
Tarantula-like (Mygalomorphae) and haplogyne real spiders , on the other hand, have relatively simply built female sexual organs that have no epigyne. While in the latter two groups the end section of the uterus opens out directly in front of the book lungs , the epigyne itself is a copulatory organ made up of several parts in front of it. It usually consists of a bulging area with invaginations extending inwards.
The paired insertion openings for the emboli represent the outer genital openings, which are sunk into the epigastric groove . During copulation, the median apophysis of the male bulb gets caught up with the scapus process of the epigyne. The embolus, which is usually rolled up in a spiral shape (the tip of the male globe), is inserted into the outer opening. The embolus unrolls and penetrates to the internal genital opening , the recaptulum seminis (spermathec) . There the sperm is pressed out of the embolus (presumably by glandular secretions) and released into the sperm library, where it can be stored for weeks or months. Shortly before the egg is laid, the sperm migrate through the fertilization ducts to the external uterus and perform fertilization there.
literature
- Rainer F. Foelix: Biology of the spiders . Georg Thieme, Stuttgart 1979, ISBN 3-13-575801-X .