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Strictly speaking, the semen-sucking mosquito does not exist. But there are plenty of mosquitoes that use an unusual method of "heterospecific mating". The female mosquitoes are equipped with special sperm-sucking tubes located at the end of their abdomens, which they use to siphon up semen from larger males--and then store it for future reproduction. The female is then able to lay her eggs directly on top of this male’s sperm — and to fertilize them with this nutritious secretion. What a bargain! It turns out that this mating system is common in the mosquitoes of the genus Anopheles , which are well known for their role in spreading malaria. It is believed to be a rather ancient system, and perhaps has evolved independently in a number of other genera of insects as well. There are at least 180 described species of Anopheles mosquitoes. Most have been known for decades, but only recently have their sperm-sucking habits been discovered by scientists—and then not just documented in scientific papers but actually filmed for the first time ever. The above video clip shows a female A. funestus mosquito laying her eggs directly on top of a male A. gambiae mosquito who has just deposited his sperm on the leaves right below her. The male's sperm is already at the larval stage, whereas the female's eggs need to be fertilized first before they can properly develop. The first to be laid are those of the first male she has mated with—the fertilization material will be transferred to her ovaries, and she will then use it as an egg-laying substrate for future males. This second male's sperm must be mixed with that of another female before they are used together to fertilize their common batch of eggs. The expert who filmed this scene, Dr. Sonja Klein of the University of Münster in Germany, reports: “Up to now we have only known the sperm-sucking system for sure for approximately 10 out of these 180 species. Now we have found it for six more genera.” Scientists actually knew that some types of mosquitoes took up sperm while others did not, but what made this new video so important was the use of fluorescent dye to show that it is stored inside special storage organs called spermathecae. "There are two different types of spermathecae," Dr. Klein explains further. "The ones that are shaped like a little ball are used for short-term storage, while the tubular ones are used for long-term storage.” By studying their mating habits in detail, scientists have discovered that female mosquitoes have developed quite a lot of "intelligent" adaptations to get the most sperm possible from males. Sometimes they even trick them into thinking they have already “mated” with other females. But however sneaky they get, it is important to remember that when it comes to avoiding disease, they aren't after blood—or human organs! The only way we can prevent malaria is by using preventive measures such as mosquito nets and insecticides. cfa1e77820
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