5 

 unknown, although they are presumed to provide information similar to that of the 



grooved pegs. Small sensilla coeloconica are at the tips of the antennae and respond 



to changes in air temperature. There are two sets of neural cells comprising the 



small coeloconica. One is activated by a temperature increase, whereas the second 



is inhibited by it. This allows a mosquito (i.e. Ae. aegypti) to sense temperature 



changes at short-range (within one meter of the host) [6]. The sensilla ampullaceae 



on the antennae are only suspected to function in temperature and humidity 



detection; no experiments as of yet confirm this. Sensilla trichodea are the most 



numerous sensilla found on the antennae. Fewer of these sensilla are present on 



male antennae compared to female antennae (for the same species). The responses 



of these sensilla vary widely in terms of olfactory detection, e.g. fatty acids, essential 



oils, oviposition compounds, and repellents. None has been found to give a response 



to lactic acid [6]. 



Sensilla found on the mosquito antennae may not be the sole location for 

 chemical reception of odor cues. The mouth may also contribute some ability for 

 chemical reception of odors and has been postulated to function in infrared detection 

 [4]. The various setae found on the mosquito body are generally mechanosensilla, 

 as are the chordotonal organs. In contrast to setae, chordotonal organs found in the 

 cuticle provide information as to the position of mosquito body parts. 



Sound detection in mosquitoes involves frequency detection by the Johnston's 

 organ in antennae [4]. Experiments involving antennae removal or impedance of the 

 Johnston's organ resulted in a lack of response of mosquitoes to sound stimuli [8]. 



