Chapter 1 Orientation Towards Hosts in Haematophagous Insects

Feel the heat: Activation, orientation, and feeding responses of bed bugs to targets at different temperatures

“…Yet, convection currents play a major role in heat detection in mosquitoes (Peterson and Brown, 1951), and their preference for vertically oriented flight has inspired the design of vertical olfactometers (Feinsod and Spielman, 1979). Moreover, in all our experiments, the heat coil remained in contact with the substrate, so it is unclear whether bed bugs responded to conductive or radiant heat, with radiant heat inducing responses in the closely related hematophagous hemipteran Triatoma infestans (Lazzari, 2009;Lazzari and Núñez, 1989b).…”

“…Lazzari and Núñez (1989b) found the kissing bug Triatoma infestans to be capable of infrared heat detection, quite different from other arthropods, which primarily rely on conduction and convection (Khan et al, 1966(Khan et al, , 1968. When orienting toward a heat source, kissing bugs were observed to use both telotaxis (orientation using a single sensory structure over longer distances) and tropotaxis (orientation using dual sensory structures over short distances) (Lazzari, 2009). Although thermotaxis for host location has received some attention in hematophagous insects, it has traditionally been evaluated in combination with other host cues (Grossman and Pappas, 1991;Khan et al, 1968;Takken and Verhulst, 2013).…”

Learning the way to blood: first evidence of dual olfactory conditioning in a blood-sucking insect, Rhodnius prolixus. I. Appetitive learning

“…This is not case for blood-sucking insects, which need to pierce the host skin before gaining access to the blood, e.g. from inside blood vessels or from a wound (Lazzari, 2009). In the case of R. prolixus, proboscis extension is not induced by blood components, but in response to heat stimulation (Lazzari and Núñez, 1989;Flores and Lazzari, 1996).…”

“…Indeed, learning and memory could improve the capacity of blood-sucking insects, by narrowing their search, aiding in the selection of targets, conserving energy as well as enhancing their resource-locating efficiency (McCall and Kelly, 2002). It should be remembered that for these bugs, a host plays the double role of prey and predator (Lazzari, 2009). Although it is adaptive to recognize and remember any cues from high-quality resources, it seems equally necessary to be able to avoid the most defensive hosts (McCall and Kelly, 2002).…”

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a major role in host-seeking behaviour in haematophagous insects (Lazzari, 2009;Guerenstein and Lazzari, 2009 Accepted 28 June 2011 SUMMARY It has been largely assumed that the individual experience of insects that are disease vectors might not only contribute to animal fitness, but also have an important influence on parasite transmission. Nevertheless, despite the invested efforts in testing the capacity to learn and remember information in blood-sucking insects, only little conclusive information has been obtained to date.

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