Copulatory behavior in a pholcid spider: males use specialized genitalic movements for sperm removal and copulatory courtship
Por:
Calbacho-Rosa, L, Galicia-Mendoza, I, Dutto, MS, Cordoba-Aguilar, A, Peretti, AV
Publicada:
1 may 2013
Categoría:
Ecology, Evolution, Behavior and Systematics
Resumen:
Sexual selection may operate on pre-copulatory, copulatory, and
post-copulatory traits. An example of a copulatory target of sexual
selection is the genitalic movements a male performs during copulation.
These movements may function either to prevent sperm competition or to
influence a female's fertilization decision. Here we investigated how
copulation duration, pedipalp movements, and abdominal movements that
males of the pholcid spider Holocnemus pluchei produce during copulation
influence sperm removal and/or patterns of successful sperm transfer. We
compared mating events with virgin and mated females for differences in
copulatory and post-copulatory behavior. We expected longer copulation
duration, longer pedipalp movement duration, and more complex and
frequent pedipalp and abdominal movements when males mated with mated
females compared to virgin females. Except for abdominal movements, our
results corroborated these predictions. Furthermore, when we
investigated mating events with mated females, we observed sperm mass
ejection from the female gonopore and physical removal of sperm by
males' procursi. Females with interrupted second mating events showed a
significant reduction of stored sperm masses compared to females with
completed mating events. We suggest that males use alternating pedipalp
movements to remove most of the rival sperm stored by mated females
prior to sperm transfer. Copulation duration and pedipalp movements can
be further used to transfer sperm and/or as a form of genitalic
copulatory courtship.
Filiaciones:
Cordoba-Aguilar, A:
Univ Nacl Autonoma Mexico, Dept Ecol Evolut, Inst Ecol, Mexico City 04510, DF, Mexico
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