The deposition of sperm by males into females requires the female to bend her abdomen such that her genitalia are in contact with the male’s secondary genitalia. Thus, before ejaculation, the male uses his penis to remove previously deposited sperm. This improves the fitness of the male in question because it maximizes his chance of spreading his genes to the greatest proportion of eggs in the female. The male penis has special structures to remove stored sperm. This can be completed while in tandem.Ĥ) Wheel position The female stores sperm from several males in her oviduct in preparation for fertilisation and oviposition. Self insemination is achieved by the male curling his abdomen so that his genitalia touch the opening of the sperm reservoir. The primary genitalia produces sperm whereas the secondary genitalia functions as a penis. For males, they are unable to partake in courtship flight or defend their territory from other males (Berger and Hansen, 2004).ģ) Self insemination Before actual copulation, males have to transfer sperm from their primary genitalia, located under abdominal segment 9, to the secondary genitalia in segment 2. This directly interferes with the reproductive success of the Odonate. If there are too many mites on an Odonate adult, they may weight the insect down preventing proper flight. The mites feed on the adult's body fluids and return to the water after obtaining sufficient food. As the adult Odonate emerges from the last larval skin, the mites attach onto the soft body of the new adult via its piercing mouthparts. The female mite lays its eggs in the water and as soon as they hatch, the young mites search for an Odonate larvae that is just about to emerge. Water mites are common parasites of Odonates. Some wasps capture Odonates, kill them, and deposit their eggs in the dead insect (Berger and Hansen, 2004). However, certain wasp species do oviposit in Odonate eggs, which the wasp larvae feeds on after it hatches (Santolamazza et al. Yellow bittern feeding on a damselflyPermission pendingBy Chris Lee, Bird Ecology Study GroupĢ) Parasitoids and parasites In general, little is known about parasitoids of Odonate eggs partly owing to the fact that Odonate eggs are often well concealed amongst the vegetation or found submerged in water.
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