Predation by adult and larval lady beetles (Coleoptera: Coccinellidae) on initial contact with lady beetle eggs

Na?ve adults and larvae of the native lady beetles Coleomegilla maculata (DeGeer), Cycloneda munda (Say), Hippodamia convergens Guérin-Méneville, Olla v-nigrum (Mulsant), and the exotic lady beetle Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) were tested for their initial response to eggs of these five lady beetle species and for egg consumption on first contact and after 3 h. Additionally, field-collected O. v-nigrum and H. axyridis adults were tested. C. maculata, H. axyridis, and O. v-nigrum adults responded similarly to all egg species on first contact. Higher numbers of C. munda adults did not eat C. maculata, H. convergens, and O. v-nigrum eggs on first contact compared with numbers that did eat C. munda and H. axyridis eggs. H. convergens adults always ate C. munda eggs but hardly ate H. axyridis eggs on first contact. Results showed that over the 3-h interval, egg predation by those predators feeding on first contact was always higher, except for adults and larvae of C. maculata, than for those that did not feed on first contact. Thus, acceptance of eggs on initial contact does impact egg survival. It is likely that eggs of all native species tested (i.e., C. maculata, C. munda, H. convergens, and O. v-nigrum), but not exotic H. axyridis eggs, are suitable food for C. maculata, H. convergens, and O. v-nigrum, whereas only C. munda eggs serve as suitable food for C. munda. In direct contrast, all egg species tested would likely serve as suitable food for the exotic H. axyridis.     

Potential for intraguild predation and competition among predatory Coccinellidae and Chrysopidae

In a laboratory study two coccinellid species, Coleomegilla maculata (DeGeer) and Harmonia axyridis Pallas, completed preimaginal development on lacewing eggs, Chrysoperla carnea Stephens or pea aphids, Acyrthosiphon pisum (Harris) in similar times. Preimaginal survival on C. carnea eggs was similar to survival on A. pisum for all stages of C. maculata and H. axyridis. Coccinellid adults that developed on C. carnea eggs were smaller than adults reared on A. pisum. Coccinella septempunctata L. did not complete preimaginal development on C. carnea eggs. Chrysoperla carnea preimaginal developmental time was approximately 20 days when fed either C. maculata eggs or A. pisum. Chrysoperla carnea fed C. maculata eggs developed into smaller adults, compared to adults reared as larvae on A. pisum, Ostrinia nubilalis (Hübner) eggs, or A. pisum alternated daily with O. nubilalis eggs. C. carnea did not complete preimaginal development on H. axyridis eggs. Cannibalism occurred more frequently between C. carnea third instars than between C. maculata fourth instars. When a C. carnea third instar was paired with a C. maculata fourth instar, more C. maculata were preyed upon by C. carnea, regardless of the herbivorous prey density. In the field these two predator species may negatively affect each other and reduce their suppression of pest densities.     

Larval feeding on Bt hybrid and non-Bt corn seedlings by Harmonia axyridis (Coleoptera: Coccinellidae) and Coleomegilla maculata (Coleoptera: Coccinellidae)

Zoophytophagy is an omnivorous activity that occurs when a primarily carnivorous species feeds on plant material. Plant feeding by beneficial predators may have negative consequences if the plant material has been chemically treated, contains toxins, or was transgenically altered. Although common in predaceous Hemiptera, zoophytophagy has been rarely studied in aphidophagous coccinellids. This study examined the likelihood of feeding on Bt and non-Bt corn seedlings by third- and fourth-instar coccinellid larvae, the regularity of feeding events by fourth instars, and the effect of leaf feeding on development time and adult size. Both third- and fourth-instar Harmonia axyridis Pallas and Coleomegilla maculata DeGeer consume leaf tissue, with fourth instars being significantly more likely to feed on corn seedlings. C. maculata larvae ingested leaf tissue more frequently than H. axyridis. Furthermore, when given access to corn seedlings daily, development time of fourth-instar C. maculata increased after Bt hybrid corn treatments compared with non-Bt corn treatments. Zoophytophagous feeding behavior is thought to sustain predators during times of low prey availability, and leaf tissue feeding by coccinellids has typically been attributed to their need for water. However, in this study, tissue feeding regularly occurred even though coccinellid larvae had constant access to water and a daily ad libitum supply of aphids. We suggest that, in addition to environmental conditions, the physiological state of the zoophytophagous species will influence the probability of plant feeding.     

Effect of cannibalism and predation on the larval performance of two ladybird beetles

The relative impact of cannibalism and predation on the development and survival of fourth instar larvae was assessed in two species of aphidophagous ladybird beetles, Coccinella septempunctata and Harmonia axyridis. The effect of eating aphids, conspecific larvae or heterospecific larvae on larval performance differed in the two species: aphids were the best food for C. septempunctata and survival of C. septempunctata larvae was significantly lower when offered heterospecific larvae rather than conspecific larvae or aphids as food, indicating that H. axyridis larvae were not suitable food for C. septempunctata. However, as the different foods did not affect the larval performance of H. axyridis, this species appears to be more polyphagous. Both intraguild predation by the aggressive larvae of H. axyridis and the polyphagous food habit of this species may account for its dominance in ladybird assemblages and its displacing other ladybird beetles in several places in the world.     

Effects of food deprivation on the development of Coleomegilla maculata (De Geer) (Coleoptera: Coccinellidae)

The lady beetle Coleomegilla maculata (De Geer) is a natural enemy of several insect pests and feeds on pollen and nectar to survive periods when prey is scarce. The effect of the feeding interval on the development, survival, fecundity, and longevity of C. maculata was determined. Newly hatched larvae of C. maculata were reared individually and fed with eggs of the Mediterranean flour moth Anagasta kuehniella (Zeller) at intervals of one, two, and three days under controlled conditions (23 ± 1oC; 60 ± 10% RH; 12 h phtophase). The duration of larval instars and the total larval stage was prolonged as the feeding interval increased. The larval period lasted on average 9.2 ± 0.19 days when the larvae were fed daily with prey, and 14.6 ± 0.48 days when food was offered at three-day intervals. There was an inverse relationship between food intervals, survival, and weight of larvae and adults of the coccinellid. Survival rate of larvae fed daily was 76.8%, while the rate was 50.0% and 23.4% for larvae fed every two and three days, respectively. Coleomegilla maculata showed fecundity of 781.1 ± 149.02, 563.4 ± 80.81 and 109.0 ± 103.0 eggs when fed daily and at intervals of two and three days, respectively.     

Response of coccinellid larvae to conspecific and heterospecific larval tracks: a mechanism that reduces cannibalism and intraguild predation

Cannibalism, where one species feeds on individuals of its own species, and intraguild predation (IGP), where a predator feeds on other predatory species, can both pose significant threats to natural enemies and interfere with their biological control of pests. Behavioral mechanisms to avoid these threats, however, could help maintain superior pest control. Here, we ask whether larvae of Coccinella septempunctata (Coleoptera: Coccinellidae) and Harmonia axyridis (Coleoptera: Coccinellidae) respond to larval tracks deposited by the other and whether this behavioral response reduces the threat of cannibalism and IGP. In petri dish experiments, we show that both H. axyridis and C. septempunctata avoid foraging in areas with conspecific larval tracks. Using a method of preventing larvae from depositing tracks, we then demonstrate that the frequency of cannibalism is greater for both species when larvae are prevented from depositing tracks compared with when the tracks are deposited. For multi-species interactions we show in petri dish experiments that C. septempunctata avoids H. axyridis larval tracks but H. axyridis does not avoid C. septempunctata larval tracks, demonstrating an asymmetry in response to larval tracks that parallels the asymmetry in aggressiveness between these species as intraguild predators. On single plants, we show that the presence of H. axyridis larval tracks reduces the risk of IGP by H. axyridis on C. septempunctata. Our study suggests that larval tracks can be used in more ways than previously described, in this case by changing coccinellid larval behavior in a way that reduces cannibalism and IGP.     

Teratocytes growth pattern reflects host suitability in a host–parasitoid assemblage

Abstract.  In some parasitoid species, the serosa membrane breaks apart at hatching and produces teratocyte cells that assume various functions (immunossupression, secretion and nutrition) mediating host–parasitoid relationships. Teratocyte growth pattern may thus reflect the host suitability for a parasitoid. The teratocyte growth pattern (increase in size and number of teratocytes as a function of time) is studied and used as an indirect measure of fitness to compare the development of the endoparasitoid Dinocampus coccinellae in a marginal host, the coccinellid Harmonia axyridis , and in a suitable host, Coleomegilla maculata . Indirect measures of fitness recorded in both host species confirm that C. maculata is a suitable host for D. coccinellae contrary to the marginal host H. axyridis. According to regression analysis, teratocyte numbers decrease linearly whereas teratocyte size increases linearly with time in the suitable host C. maculata (larvae or adults). In the marginal host, parasitism occurs only in the larval stage where a delay in the parasitoid larval development is observed. Increase in teratocyte size is also highly variable. The teratocyte growth pattern of the parasitoid in the marginal host does not follow the linear model found in the suitable host. Teratocyte growth pattern may be a useful criterion to evaluate host-suitability and host range of parasitoids.     

Effects of biorational pesticides on four coccinellid species (Coleoptera: Coccinellidae) having potential as biological control agents in interiorscapes

The direct toxicity of insecticidal soap, horticultural oil, Azatin, an extract from the Neem tree containing azadiractin, and BotainiGard, a commercial formulation of the entomopathogenic fungus Beauveria bassiana, was assessed on adults of four species of coccinellids--Hippodamia convergens (Guérin-Ménéville), Coleomegilla maculata (DeGeer), Harmonia axyridis Pallas, and Cryptolaemus montrouzieri Mulsant. All biorationals caused less mortality than a conventional pesticide, carbaryl (Sevin). Horticultural oil (Sunspray ultrafine oil) consistently had no effect on beetle survivorship. Insecticidal soap (M-Pede) significantly reduced survival in all replicates for C. maculata and in at least one of the three replicates for the other three coccinellid species. Beauveria bassiana (BotaniGard) significantly reduced survival of C. montrouzieri at 72 h after spray in all three replicates. Azatin reduced survivorship in only one species, C. maculata, in only one of the three replicates.     

Intraguild predation among ladybeetles and a green lacewing: do the larval spines of Curinus coeruleus(Coleoptera: Coccinellidae) serve a defensive function?

Laboratory experiments examined interspecific interactions between larvae of three coccinellid species, Curinus coeruleus Mulsant (Chilocorinae), Harmonia axyridis Pallas and Olla v-nigrum (Mulsant) (Coccinellinae), and between these and larvae of the green lacewing, Chrysoperla rufilabris (Burmeister). Larvae of C. coeruleus, although defended on their dorsal surface with long spines, had the smallest mandibles, were the slowest-moving, and the least successful in interspecific larval combat. The long spines of third instar C. coeruleusappeared to reduce their palatability as food to H. axyridis and O. v-nigrum larvae in choice tests with dead larvae, but were not an effective defence against these species in Petri dish arenas. Larvae of O. v-nigrum had a smooth dorsal surface, were intermediate in terms of mandible size, but were the fastest moving, a trait that benefited their survival in intraguild combat. Larvae of H. axyridis were intermediate with respect to dorsal spines and speed of movement, but had the largest mandibles. This species was the most effective intraguild combatant among the coccinellids and the only one to successfully compete against C. rufilabris larvae of similar age. The speed, manoeuverability and long mandibles of C. rufilabris enabled them to impale coccinellid larvae at a relatively safe distance. The spines of C. coeruleus larvae impeded laterally oriented attacks by C. rufilabris, but did not provide sustained protection from repeated attacks. Success in these interactions appeared largely a function of offensive weaponry (mandible size and morphology) and speed of movement, although the role of dorsal spines as defensive structures was not ruled out. Rates of larval cannibalism were highest for C. rufilabris and largely mirrored the level of aggression observed in interspecific combat for each species.     

A comparative study of larval cannibalism in three species of ladybird

Abstract. 1. Cannibalism was studied under laboratory conditions in three species of Coccinellidae (Coleoptera): Cycloneda sanguinea , Olla v-nigrum , and Harmonia axyridis . Larval cannibalism varied among species, C. sanguinea  > H. axyridis  ≥  O. v-nigrum .
2. Larvae of all species cannibalised more in response to reduced food availability (14 h starvation daily) than in response to reduced food quality (dry Ephestia eggs).
3. Larvae of H. axyridis cannibalised siblings at lower rates than non-siblings, but larvae of C. sanguinea and O. v-nigrum did not. Rates of cannibalism increased significantly with increasing size disparity among larvae of all three species.
4. Cannibalism in C. sanguinea and H. axyridis , but not in O. v-nigrum , increased with larval density, suggesting that not all attacks on conspecifics are driven by hunger.
5. Costs, not benefits, were the predominant effects of exclusively and partially cannibalistic diets. A diet of conspecific eggs yielded survival equivalent to the Ephestia egg diet for H. axyridis and O. v-nigrum , but developmental time was extended and adults were smaller. Larvae of C. sanguinea had superior survival and faster development on conspecific eggs than on the Ephestia egg diet. Only H. axyridis larvae survived as well on diets comprised exclusively or partially of conspecific larvae as on Ephestia eggs, although they developed more slowly.     

Effect of corn hybrids expressing the coleopteran-specific cry3Bb1 protein for corn rootworm control on aboveground insect predators

Field and laboratory studies were conducted to determine the effect of transgenic Bacillus thuringiensis (Bt) corn, Zea mays L. (YieldGard Rootworm), expressing the Cry3Bb1 protein on aboveground nontarget insect predators (minute pirate bug, ladybird beetles, and carabids). Visual counts of adult and immature Orius insidiosus (Say), Coleomegilla maculata (DeGeer), Hippodamia convergens Gurin-Meneville, and Scymnus spp. occurring in Bt corn and its non-Bt isoline were made at Manhattan, KS, in 2002 and at Manhattan and Scandia, KS, in 2003. No significant differences were found between the Bt corn and non-Bt isoline plots in the abundance (number per plant) of O. insidiosus, C. maculata, H. convergens, and Scymnus spp. Field predation on Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae) egg masses was also observed during the silking stage of corn at Manhattan and Scandia in 2003. No significant differences were observed among treatments in predation rate for predators with chewing versus sucking mouthparts. Two laboratory studies determined the effect of Cry3Bb1 protein expressed in Bt corn pollen on C. maculata and carabids. The larvae of C. maculata were reared on Bt pollen, non-Bt pollen, or greenbugs, Schizaphis graminum (Rondani). The duration of larval and pupal stages, developmental time from egg hatch to adult emergence, percentage of survival, and elytra length were compared among treatments. There were no significant differences in developmental time of larvae fed pollen or greenbugs during their first two instars. However, significantly prolonged development of the third (1 d) and fourth instars (2 d) was observed for larvae fed greenbugs only. Total time for larval development was significantly longer for larvae that fed on greenbugs versus larvae fed on pollen. No significant differences were observed among treatments in the percentage of larvae that pupated or pupal stage duration. Larvae that fed on greenbugs had higher pupal and adult weights compared with pollen-fed larvae. However, pupal and adult weights did not vary between the Bt and non-Bt pollen treatments. No significant differences occurred in longevity and elytra length of beetles among all treatments. Two carabid species, Harpalus caliginosus F. and Harpalus pensylvanicus DeGeer, were reared on moistened dog food sprinkled with Bt or non-Bt corn pollen. No significant differences in mortality of H. caliginosus and H. pensylvanicus were detected among any of the treatments. There was no significant effect of Bt pollen on fecundity and egg viability of H. caliginosus. Our studies showed that YieldGard Rootworm had no effect on the selected coleopteran predators; therefore, this Bt corn hybrid could be used in an integrated pest management system.     

Effects of starvation on larval growth, survival, and metamorphosis of Manila clam Ruditapes philippinarum

The effects of starvation on larval growth, survival, and metamorphosis of Manila clam Ruditapes philippinarum at the temperature of 19.6–21.6 °C, the salinity of 34‰ and pH of 8.0 were investigated from May 18 to July 18, 2006. In this study, the early, middle and late umbo-veliger larvae with the shell lengths of 100, 140, and 190 μm were subject to temporary food deprivation for up to 4.5, 20, and 25d at 0.5, 4, 5d intervals, followed by refeeding for the remaining of a 24, 20, 25d period, respectively. The results suggested that the larvae should have shown considerable tolerance to starvation due to their endogenous and exterior nutrition material, for larvae and time to the point-of-no-return (PNR: the threshold point during starvation after which larvae could no longer metamorphose even if food is provided) were calculated to be 4.25, 17.54, and 22.17d. As the starvation period prolonged, the mean shell length of larvae starved got close to constants at 1.5, 4, and 15d after starvation, which were different for larvae at different stages when starvation began, survival of larvae decreased, and was lower in treatments starved earlier in development than those starved later, for the early, middle and late umbo-veliger larvae, after 4.5, 20 and 25d of starvation period, few larvaes were alive. After starvation period, the alive larvaes were able to metamorphose and had a capability of compensatory growth when refeeding was given. Starvation not only affected metamorphosis rate, but also caused the delay in the time to metamorphosis and the decrease in the metamorphosed sizes. For example, for the continuously-fed larvae, duration to metamorphosis was 20.7d, for larvae with a size of 100-μm starved for up to 4d, larvae with a size of 140-μm starved for up to 16d, larvae with a size of 190-μm starved for up to 20d, duration to metamorphosis were 29.7, 31.7, and 37.7d, the delay in duration to metamorphosis were 9, 11, and 17d, respectively. Furthermore, importance of nutrition material for maintaining larval survival during starvation and the compensatory growth on larvae at the same feeding time were discussed.     

Insights into How Longicorn Beetle Larvae Determine the Timing of Metamorphosis: Starvation-Induced Mechanism Revisited

Larvae of holometabolous insects must determine the timing of their metamorphosis. How they determine this timing has only been studied in detail for a few insect species. In a few species of Coleoptera, starvation is known to be a cue for metamorphosis, leading to the formation of smaller adults (starvation-induced pupation, SiP). We investigated the occurrence of SiP in the beetle Psacothea hilaris. When P. hilaris larvae were starved late in the feeding phase of the last (5th) instar, they exhibited typical SiP characterized by constancy of the time from food deprivation to pupation (TTP) irrespective of the body weight upon food deprivation or the length of prior feeding. In contrast, when larvae were starved early in the feeding phase, TTP decreased by roughly 1 day as the feeding became 1 day longer. The change in the response to starvation was estimated to occur on day 5.9 in the last instar. A series of refeeding experiments suggested that whereas SiP occurred readily in the larvae starved in the late feeding phase, activation of SiP was suspended until day 5.9 in the larvae starved early in the feeding phase. When P. hilaris larvae were fed continuously, they eventually ceased feeding spontaneously and pupated. The time length between spontaneous cessation of feeding and pupation was approximately equal to the TTP in SiP. This suggests that the same mechanism was activated by food deprivation in the late feeding phase and by spontaneous cessation of ad libitum feeding.     

Relationships Between Attack and Escape Rates, Cannibalism, and Intraguild Predation in Larvae of Two Predatory Ladybirds

We compared incidences of cannibalism and intraguild (IG) predation (IGP) and quantified attack and escape rates—mechanisms which possibly account for the difference in incidences of these interactions—in laboratory experiments with Harmonia axyridis and Coccinella septempunctata. There was a tendency for H. axyridis to act as an IG predator and C. septempunctata as an IG prey. Cannibalism was also often observed in both species. The incidences of both IGP and cannibalism were different between the species. The average attack rates of C. septempunctata were less than 20%, but those of the more aggressive H. axyridis exceeded 50%. Larvae of both species attacked conspecifics and heterospecifics H. axyridis larvae successfully escaped when attacked by both conspecifics and by heterospecifics, while larvae of C. septempunctata escaped from attacks of conspecifics but not from those of heterospecifics. Thus the aggressive behavior of H. axyridis, in particular, of the third and fourth instars, negatively affects the larval survival of C. septempunctata. It may contribute to the dominance of H. axyridis in ladybird assemblages and its displacement of other ladybird species in several places in the world.     

The impact of food type, temperature and starvation on larval development of Balanus amphitrite Darwin (Cirripedia: Thoracica)

The impact of diatom food species (Chaetoceros calcitrans and Skeletonema costatum), temperature and starvation on the larval development of Balanus amphitrite was evaluated. Starvation threshold levels for different ages of larvae (0- to 5-day-old) fed with C. calcitrans and S. costatum and then starved at 5, 15 and 25 °C temperature were estimated as ultimate recovery hour (URH; denoting the starvation point in hours at the end of which larvae can recover and continue development). Effect of temperature on starvation threshold varied significantly with larval age and food species. The URH declined with larval age at 5 °C, but not at 15 and 25 °C. The URH and grazing rates were high for early instars fed on C. calcitrans, and for advanced instars fed on S. costatum. Carbon gain through feeding was maximum for 2-day-old larvae when fed with C. calcitrans and decreased with larval age. However, when fed with S. costatum carbon gain increased with larval age. This confirms that with development the utility of food types changes. The differences in the carbon gain can be attributed to differences in grazing rate due to variations in the size of the diatom cells, larval intersetular distance, diatom sinking rate and the photo-taxic behavior of larvae. Molting was observed at times when larvae were undergoing starvation and this could be viewed as stress-induced molting, and it differed with the larval age and food organisms.     

Nutritional plasticity of the predatory ladybeetle Harmonia axyridis (Coleoptera: Coccinellidae): comparison between natural and substitution prey

The predatory coccinellid Harmonia axyridis is a polyphagous species, efficient at controlling certain aphid species and already commercialized in Europe for that purpose. The complete development of this predator can be accomplished using the aphid Acyrthosiphon pisum or Ephestia kuehniella eggs as substitution prey. Biochemical analyses were conducted on the proteins, lipids, and carbohydrates of these two different prey species. E. kuehniella eggs were 2 times richer in amino acids than A. pisum adults (12% of the fresh weight vs. 6%). E. kuehniella eggs were 3 times richer in lipids than the aphids but, on the contrary, the aphids were 1.5 times richer in glycogen. The impact of these two kinds of food on the body composition of the coccinellid was evaluated to appreciate the degree of nutritional plasticity of the coccinellid. The composition of the coccinellids feeding either on E. kuehniella eggs or on aphids was compared for amino acid, fatty acid and glycogen contents, revealing a good capability of H. axyridis to develop on foods that are very different in their biochemical composition. Nevertheless, when fed on aphids, the crude protein content of the predator was reduced and the lipid content decreased by a factor of two, with a change in amino and fatty acid patterns. Some biological parameters, such as larval mortality, adult weight, and fecundity, were modified according to the food eaten.     

Juvenile hormone titres and metabolism during starvation-induced supernumerary larval moulting of the tobacco hornworm, Manduca sexta L.

When tobacco hornworm (manduca sexta) larvae are starved for 5 days immediately after ecdysis to the 5th instar, then fed normal diet, they undergo a supernumerary moult instead of metamorphosis. During starvation the titre of juvenile hormone in the haemolymph increased to a maximum of 3 ng juvenile hormone I equivalents/ml (determined by the black Manduca larval bioassay) on the fourth day of starvation, then began a decline which continued through the subsequent feeding period. The changes in juvenile hormone titre were not attributable to changes in haemolymph volume during starvation (only a 5% decrease) and subsequent feeding. During starvation the esterase activity of the haemolymph declined 4-fold with a 2-fold larger decrease in the DFP-insensitive, presumably juvenile hormone specific, esterase activity. Both the total and the juvenile hormone-specific esterase activity then increased as a function of larval weight during the subsequent feeding period. As growth was slow in the prolongedly starved larvae, sufficient juvenile hormone was present at the time of prothoracicotropic hormone (PTTH) and ecdysteroid release at the beginning of the fourth day of feeding to prevent metamorphosis.     

Intraguild predation of the aphid pathogenic fungus Pandora neoaphidis by the invasive coccinellid Harmonia axyridis

Abstract.  1. The ladybird Harmonia axyridis is an invasive alien species in many countries and is predicted to have a negative impact on native biodiversity. However, little is known on the status of this aphidophage as an intraguild predator of natural enemies of aphids such as insect-pathogenic fungi.
2. The study assessed the predation of the aphid-specific pathogenic fungus Pandora neoaphidis by adult and larval H. axyridis collected from the U.K. (an invasive population) and Japan (a native population) relative to that of the ladybird Coccinella septempunctata (native to the U.K.) and the non-U.K. C. septempunctata subspecies brucki that were either starved or unstarved.
3. Overall, predation of uninfected aphids was greater than infected aphids and, when given a choice, a preference for aphids was shown. However, the extent of this preference was dependent on the species and origin of the coccinellid. Harmonia axyridis (U.K.) consumed the greatest quantity of fungal cadavers and showed little preference for uninfected aphids over infected aphids. In contrast, C. septempunctata rarely consumed infected aphids. Life stage had no direct effects on predation but starved coccinellids consumed more uninfected aphids than infected aphids.
4.  Harmonia axyridis (U.K.) is a stronger intraguild predator of P. neoaphidis cadavers than the native species C. septempunctata and, therefore, may have an impact on the occurrence and persistence of P. neoaphidis . The differences in intraguild predation by H. axyridis collected in the U.K. and those from Japan suggests that individuals that invaded the U.K. could have a different genetic profile to those in its native range.