Intraguild predation between syrphids and mirids: who is the prey? Who is the predator?

Abstract

The mirid Macrolophus caliginosus Wagner (Hemiptera: Miridae), and the syrphids, Sphaerophoria rueppellii (Wiedemann), Sphaerophoria scripta (L.), and Episyrphus balteatus (DeGeer) (Diptera: Syrphidae), belong to the aphidophagous guild, feeding on aphids (Hemiptera: Aphididae) in Mediterranean vegetable crops. The direction, symmetry, and intensity of intraguild predation between different instar combinations of syrphids and mirid were studied in an arena without plants. Moreover, predatory interactions between syrphids and mirids on plants were also evaluated. The results obtained in the arena without plants demonstrated mutual intraguild predation, i.e., syrphid eggs were highly susceptible to predation, whereas mirid nymphs and adults were attacked by syrphid larvae. All syrphid species showed the same propensity to predation, which was unaffected by parasitism of syrphid larvae by Diplazon laetatorius (Fabricius) (Hymenoptera: Ichneumonidae). Sphaerophoria scripta eggs were less susceptible to predation than those of the two other syrphid species. The experiment performed on plants showed different results. Predation by syrphid larvae on mirids never exceeded 10%, while 100% of syrphid eggs were preyed upon after 48 h. Intraguild predation rates were not influenced by the presence or absence of aphids on the plants. This study demonstrated that results obtained from studying intraguild predation in arenas that are highly artificial should be interpreted cautiously. Depending on the colonization history of a particular habitat in the field, syrphids should be more vulnerable to predation by mirids than vice versa.

Prey of two species of jumping spiders in the field

“…Thus, IGP between jumping spiders is not as asymmetric as commonly assumed in theoretical models, but rather, they are mutual. Similar findings are reported in other taxonomic groups (e.g., Nakata and Goshima, 2005;Frechette et al, 2007). As IGP is common in generalist predators, mutual IGP may have more general characteristics than previously thought.…”

Dealing with food shortage: larval dispersal behaviour and survival on non‐prey food of the hoverfly Episyrphus balteatus

“…Larvae of different aphidophagous hoverflies were found to prey to some extent on other soft-bodied prey as well, such as thrips, whiteflies, mealybugs and springtails (Rojo et al, 2003;Gomez-Polo et al, 2015). Studies on intraguild predation further show that hoverfly larvae are able to consume other non-aphid prey if these insects are small enough to be caught (Hindayana, 2001;Fréchette et al, 2007). Thus, it is likely that hoverfly larvae would prey mostly on small insects that they encounter during their search for aphids and might only consume non-prey food to avoid starvation.…”

Effect of size, extraguild prey and habitat complexity on intraguild interactions: a case study with the invasive ladybird Harmonia axyridis and the hoverfly Episyrphus balteatus

“…Moreover, when larvae of the ladybird were combined with predators of similar size, H. axyridis remained the intraguild predator in most of the cases (Cottrell and Yeargan 1998;Kajita et al 2000;Snyder and Ives 2003;Félix and Soares 2004;Gardiner and Landis 2007;Ware and Majerus 2008). Larvae of E. balteatus were found to act as intraguild predators on smaller nymphs of Macrolophus caliginosus (Hemiptera: Miridae) (Frechette et al 2007), and on smaller larvae of Coccinella septempunctata L. (Coleoptera: Coccinellidae) (Hindayana et al 2001). …”