Which of the following statements is true regarding Toxorhynchites mosquitoes?

The statement regarding Toxorhynchites mosquitoes that is true is that they mainly feed on nectar. Unlike many other mosquito species that are known for their blood-feeding habits, Toxorhynchites, often referred to as "mosquito predators," do not require blood meals for reproduction. Instead, the adults predominantly feed on nectar from flowers, which provides them with the energy necessary for their activities. This characteristic sets them apart from many other mosquitoes that rely on blood for nourishment and reproduction.

In addition to their feeding habits, Toxorhynchites mosquitoes play an important role in the ecosystem as natural predators of other mosquito larvae, contributing to biological control of mosquito populations. This predatory behavior helps mitigate the numbers of disease-carrying mosquitoes.

The other statements do not align with the characteristics of Toxorhynchites mosquitoes. They are not aggressive; in fact, they are relatively harmless to humans since they do not feed on blood. Their lifespan is also not notably short compared to other mosquito species, and they do not represent a species group where blood feeding is a common behavior. This information is crucial for understanding the ecological role of this unique mosquito genus and dispelling common myths about mosquitoes in general.