Cannibalism and intraguild predation between endemic and introduced coccidophagous lady beetles (Coleoptera: Coccinellidae)

Abstract

The Chilocorini lady beetles Tenuisvalvae notata (Mulsant) and Cryptolaemus montrouzieri Mulsant are important biological control agents being able to share their habitat and compete for their preferred prey, mealybugs. Whereas T. notata is native to South America, C. montrouzieri is an Australian species introduced in Brazil in a biological control program of mealybugs. This work investigated the cannibalism and intraguild predation between these species in the absence of prey. To test for intraguild predation, one individual larva (instars 1-4) from each species was confined for 24 h with another larva of the same instar or the next instar, in a total of 10 combinations. In addition, we measured predation of T. notata adults upon eggs, larvae, pre-pupae and pupa of C. montrouzieri, and vice versa. Cannibalism within the species was also tested across adults, larvae and eggs. Results showed asymmetric interactions in favour of C. montrouzieri, which acted as intraguild predator more than 80% of the time when paired with larvae of T. notata either of the same or different instar. In addition, C. montrouzieri adults preyed more upon larvae and eggs of T. notata than the contrary. There was no intraguild predation upon pre-pupae and pupae. Cannibalism was high upon eggs and first instar larvae of T. notata (89.5% and 65%) and C. montrouzieri (100% and 55%), respectively. Therefore, the exotic C. montrouzieri outcompeted the native T. notata and could become a threat to this endemic species in areas of simultaneous occurrence and under prey scarcity. Thus, the interactions between these lady beetles could affect the success of biological control of mealybugs.

Footprints of the lady beetles Cryptolaemus montrouzieri and Tenuisvalvae notata affect their foraging behavior and predation rate

“…The coccidophagous lady beetles C. montrouzieri and T. notata have been used to control mealybugs in Brazil and other countries in both tropical and temperate climates (Chakupurakal et al, 1994; Maes et al, 2015). These lady beetle species may occur in the same area, as they have similar food preferences and thermal requirements (Ferreira et al, 2020), and in cases of prey scarcity, they may compete for food and have negative interactions such as cannibalism and intraguild predation (Oliveira et al, 2022). To avoid this competition, these lady beetles can use the chemical cues released in the footprints of possible competitors to avoid territory that is already occupied.…”

“…The possible attraction of C. montrouzieri to footprints of T. notata , as identified in this work, may be related to its capacity to locate the competitor in the same area, and might indicate possible negative effects of the exotic species C. montrouzieri on the indigenous T. notata . Oliveira et al (2022) showed that when food is scarce, C. montrouzieri behaves as an intraguild predator on T. notata immature stages. In contrast, T. notata spent less time on areas treated with the footprints of C. montrouzieri , suggesting that T. notata , an inferior competitor compared to C. montrouzieri , would tend to avoid such areas to avoid predation.…”

“…Therefore, even under conditions of food abundance such as those tested in this study, the ability to recognize the presence of a competitor via semiochemicals left on the substrate may result in a reduction in male C. montrouzieri predation of preferred prey (scale insects). Cryptolaemus montrouzieri is described as a superior competitor because it feeds on more prey and generally acts as an intraguild predator when in contact with other natural enemies (Chong & Oetting, 2007; Mustu et al, 2008; Dinesh & Venkatesha, 2014; Oliveira et al, 2022). However, by perceiving tracks of competitors in the area, males will be induced to feed less, engaging instead in behaviors that help them to avoid competition.…”

Dynamics Twin Cannibalism of Two Predator and Two Prey System with Prey Defense

“…Many special cases of cannibalism occur also not because of the availability of food, it actually occurs naturally. In prey, most species avoid predation interactions with predators [11] [12]. Predation interactions are considered a threat that can lead to fear and resistance.…”