Genital movements are not restricted to spermatozoa transfer in a haplogyne spider

CALBACHO ROSA, LUCIA; CARGNELUTTI, FRANCO; PERETTI, ALFREDO V.

ETHOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2021

0179-1613

Internally fertilized animals are characterized by the transfer of their spermatozoaduring copulation. However, the duration of copulation is highly variable, which suggeststhat they may serve for other functions apart from spermatozoa transfer. Forexample, during copulation, males can stimulate the female by using genitalic movementsand/or by positioning their spermatozoa adequately within the female genitalia.In the spider Holocnemus pluchei, males perform strong squeezes and torsionmovements with their pedipalps (part of their genitalia actively related to copulation)inside the female genitalia and transfer their spermatozoa during Phase I of copulation.However, the exact moment in which such transfer occurs and its relation tothe pedipalp movements are still unknown. Herein, we first have identified the precisemoment when the spermatozoa transfer occurs during phase I and its relation togenital movements by interrupting mating couples at the beginning, at middle and atend of this phase. Subsequently, the spermatozoa number remaining in male genitaliaand stored in female genitalia were counted. We detected no relation between thenumber of genital movements and the spermatozoa number present in both, femaleand male genitalia and body size. As stated above, male genital movements serveanother role during copulation in addition to spermatozoa transfer in a context ofpost-copulatorysexual selection; most likely, they stimulate the female in a crypticfemale choice framework.