Final answer:
Anopheles mosquitoes, like Anopheles gambiae, are identified by having palps that are the same length as their proboscis, a feature that differentiates them from other mosquitoes and is associated with their role in spreading malaria.
Step-by-step explanation:
Anopheles mosquitoes, specifically Anopheles gambiae, are known vectors for the transmission of malaria. The distinguishing feature of Anopheles compared to other mosquitoes in the dichotomous key is that they have palps that are the same length as their proboscis. This differentiates them significantly from other mosquitoes, which may have shorter palps in comparison to their proboscis. The characteristic of having palps as long as their proboscis is specifically mentioned in the dichotomous key that identifies different species of mosquitoes.
The length of the palps is an evolutionary adaptation that has implications for the mosquito's lifestyle and feeding behavior. In contrast to other mosquito genera that may have shorter palps, which could suggest different feeding or sensory adaptations, the longer palps in Anopheles mosquitoes could be associated with their role in spreading malaria caused by the Plasmodium falciparum parasite.