Host acceptance behaviour of a predatory pentatomid, Eocanthecona Furcellata (wolff) (Heteroptera: Pentatomidae) towards larvae of Spodoptera Litura (Lepidoptera: Noctuidae)

Abstract

Factors stimulating host seeking behaviour of Eocanthecona furcellata (Wolff), a pentatomid predator, were investigated by using Spodoptera litura (Lepidoptera: Noctuidae) as prey. Faeces of S. litura larvae elicited a host seeking response by the predators. The active material is present in the prey mandibular gland secretions, digestive tract and body surface, which when placed on a filter paper evoked feeding attempts. Predators responded intensely towards the prey artificial diet too. Prey body washings with hexane and acetone also stimulated feeding behaviour.Physical stimuli such as host shape or movement had no influence on acceptability of the prey to the predator. Larval size correlated with aggressive behaviour which limited predation rather than releasing stimulus for the host acceptance behaviour. Pharate instar stage of the prey was never accepted by E. furcellata. But pupal, egg and adult stages of 5. litura stimulated predators to certain extent.Neither extirpation of antennae nor blinding the vision prevented the bugs from locating the prey. However, excision of rostral tip decreased the prey capture efficiency. It is suggested that the rostral tip contains chemotactile sensillae which are responsible for the prey detection.

Ultrastructural Variations of Antennae and Labia Are Associated with Feeding Habit Shifts in Stink Bugs (Heteroptera: Pentatomidae)

“…furcellata and some other Asopinae species [4,30]; they have gradually tapered tips and swollen bases (Figure 5A,B) and possibly play an important role in prey detection and orientation. Labial sensilla of heteropterans are crucial in responding to olfactory and gustatory signals, and excision of the labial apex strongly decreases the ability of prey orientation and capture efficiency [49]. In the present study, we found that the type and arrangement of labial sensilla seem to be differentiated between phytophagous and predatory species.…”

“…Labial sensilla of heteropterans are crucial in responding to olfactory and gustatory signals, and excision of the labial apex strongly decreases the ability of prey orientation and capture efficiency [ 49 ]. In the present study, we found that the type and arrangement of labial sensilla seem to be differentiated between phytophagous and predatory species.…”

“…Moreover, the shape of labial cuticular projections varies greatly across pentatomid species with different feeding habits. They are short and slightly branched in plant feeders ( Figure 5 C,D and Figure 6 A–D) but long and multi-branched in predators ( Figure 5 A,B) [ 4 , 29 , 30 , 49 ]. Although various function speculations of cuticular projections have been proposed (e.g., hygroreception, mechanoreception, and cleaning) [ 4 , 29 , 49 ], their actual utility remains to be tested experimentally.…”

“…They are short and slightly branched in plant feeders ( Figure 5 C,D and Figure 6 A–D) but long and multi-branched in predators ( Figure 5 A,B) [ 4 , 29 , 30 , 49 ]. Although various function speculations of cuticular projections have been proposed (e.g., hygroreception, mechanoreception, and cleaning) [ 4 , 29 , 49 ], their actual utility remains to be tested experimentally. In C. divaricata and S .…”

“…They are short and slightly branched in plant feeders (Figures 5C,D and 6A-D) but long and multi-branched in predators (Figure 5A,B) [4,29,30,49]. Although various function speculations of cuticular projections have been proposed (e.g., hygroreception, mechanoreception, and cleaning) [4,29,49], their actual utility remains to be tested experimentally. In C. divaricata and S. lurida, the labial apex of all of the examined samples was covered with contaminants and difficult to be cleaned to show the shape of labial sensilla and cuticular projections; therefore, the labial apex of these two species is not illustrated in the present study.…”