A sensillum (plural sensilla) is an arthropodsensory organ protruding from the cuticle of exoskeleton, or sometimes lying within or beneath it. Sensilla appear as small hairs or pegs over an individual's body. Inside each sensillum there are two to four sensory neurons. These neurons, or receptors, gather information about environment the arthropod is in:[1]
^Steinbrecht, Rudolf Alexander (2007). "Structure and Function of Insect Olfactory Sensilla". Ciba Foundation Symposium 200 - Olfaction in Mosquito-Host Interactions. Novartis Foundation Symposia. Vol. 200. pp. 158–183. doi:10.1002/9780470514948.ch13. ISBN9780470514948. ISSN1935-4657. PMID8894297.