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Michael E N Majerus - One of the best experts on this subject based on the ideXlab platform.
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adaptations of Coccinella magnifica a myrmecophilous coccinellid to aggression by wood ants formica rufa group ii larval behaviour and ladybird oviposition location1
European Journal of Endocrinology, 2003Co-Authors: John J Sloggett, Michael E N MajerusAbstract:Like adults, larvae of the myrmecophilous ladybird Coccinella magnifica are rarely attacked by Formica rufa ants on foraging trails, but more often attacked on ant-tended aphid colonies. Larvae of the non-myrmecophile Coccinella septempunctata, to which C. magnifica was compared, were more readily attacked by ants in both situations. To avoid or counter ant aggression when foraging for aphids, C. magnifica larvae exhibit three main tactics: they may feed on un- or non-tended aphids; when feeding on tended colonies they often carry prey away, minimising time spent there; and if attacked, they use limited chemical defence. No novel behaviours were found in C. magnifica larvae, not occurring to some extent in C. septempunctata. Coccinella magnifica eggs were laid distant to ant-tended aphids, although closer to un- or non-tended aphids.
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aphid mediated coexistence of ladybirds coleoptera coccinellidae and the wood ant formica rufa seasonal effects interspecific variability and the evolution of a coccinellid myrmecophile
Oikos, 2000Co-Authors: John J Sloggett, Michael E N MajerusAbstract:It is generally believed that most homopteran-eating insects avoid ant-tended colonies of Homoptera, due to the ant aggression they encounter there. However, because homopteran colonies which are ant-tended often persist for longer than untended colonies, some homopteran-eaters may utilise ant-tended Homoptera when untended colonies are scarce. Furthermore, a few homopteran-eaters are myrmecophilous, habitually coexisting with ants. To investigate these phenomena, a study was made of aphids and aphidophagous coccinellids (ladybirds) on Scots pine, Pinus sylvestris, growing in areas foraged and unforaged by the wood ant Formica rufa. The non-tended aphid Schizolachnus pineti exhibited a marked population decline in late summer but persisted in both areas at very low density. Facultatively tended Cinara aphids exhibited higher population densities when associated with F. rufa, and remaining colonies of these aphids were only found associated with ants in late summer. Coccinellids exhibited considerable interspecific variability in their level of association with F. rufa, and there was some evidence of an increase in certain species’ frequencies of occurrence with the ant when Cinara aphids were all ant-tended, in late summer. Coexistence with ants appears to be associated with either an intolerance of low aphid densities, in Coccinella septempunctata and Harmonia quadripunctata, or with extreme dietary specialisation, in Myzia oblongoguttata. Similar factors to those which bring C. septempunctata into contact with ants were probably of importance in the initial stages of the evolution of myrmecophily of its congener, Coccinella magnifica.
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adaptations of Coccinella magnifica redtenbacher a myrmecophilous coccinellid to aggression by wood ants formica rufa group i adult behavioral adaptation its ecological context and evolution
Journal of Insect Behavior, 1998Co-Authors: John J Sloggett, Richard A Wood, Michael E N MajerusAbstract:Coccinella magnifica is an obligate associate of Formica rufa-group ants. The congener Coccinella septempunctata can serve as a model for its nonmyrmecophilous ancestor. Formica rufa behavior toward these two ladybirds, and their behavior, was compared. Although C. magnifica was rarely attacked on ant trails, it was usually attacked on tended aphid colonies. Coccinella septempunctata was more readily attacked. The two ladybirds' behavior was similar on trails, but C. magnifica used more defense and C. septempunctata more rapid escape behavior on aphid colonies. Only C. magnifica fed upon tended aphids. Chemical adaptation to overcome ant aggression probably exists in C. magnifica, but it possesses almost no novel behaviors to counter ant aggression. Instead, modifications have occurred in the expression of behaviors present in C. septempunctata.
John J Sloggett - One of the best experts on this subject based on the ideXlab platform.
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adaptations of Coccinella magnifica a myrmecophilous coccinellid to aggression by wood ants formica rufa group ii larval behaviour and ladybird oviposition location1
European Journal of Endocrinology, 2003Co-Authors: John J Sloggett, Michael E N MajerusAbstract:Like adults, larvae of the myrmecophilous ladybird Coccinella magnifica are rarely attacked by Formica rufa ants on foraging trails, but more often attacked on ant-tended aphid colonies. Larvae of the non-myrmecophile Coccinella septempunctata, to which C. magnifica was compared, were more readily attacked by ants in both situations. To avoid or counter ant aggression when foraging for aphids, C. magnifica larvae exhibit three main tactics: they may feed on un- or non-tended aphids; when feeding on tended colonies they often carry prey away, minimising time spent there; and if attacked, they use limited chemical defence. No novel behaviours were found in C. magnifica larvae, not occurring to some extent in C. septempunctata. Coccinella magnifica eggs were laid distant to ant-tended aphids, although closer to un- or non-tended aphids.
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aphid mediated coexistence of ladybirds coleoptera coccinellidae and the wood ant formica rufa seasonal effects interspecific variability and the evolution of a coccinellid myrmecophile
Oikos, 2000Co-Authors: John J Sloggett, Michael E N MajerusAbstract:It is generally believed that most homopteran-eating insects avoid ant-tended colonies of Homoptera, due to the ant aggression they encounter there. However, because homopteran colonies which are ant-tended often persist for longer than untended colonies, some homopteran-eaters may utilise ant-tended Homoptera when untended colonies are scarce. Furthermore, a few homopteran-eaters are myrmecophilous, habitually coexisting with ants. To investigate these phenomena, a study was made of aphids and aphidophagous coccinellids (ladybirds) on Scots pine, Pinus sylvestris, growing in areas foraged and unforaged by the wood ant Formica rufa. The non-tended aphid Schizolachnus pineti exhibited a marked population decline in late summer but persisted in both areas at very low density. Facultatively tended Cinara aphids exhibited higher population densities when associated with F. rufa, and remaining colonies of these aphids were only found associated with ants in late summer. Coccinellids exhibited considerable interspecific variability in their level of association with F. rufa, and there was some evidence of an increase in certain species’ frequencies of occurrence with the ant when Cinara aphids were all ant-tended, in late summer. Coexistence with ants appears to be associated with either an intolerance of low aphid densities, in Coccinella septempunctata and Harmonia quadripunctata, or with extreme dietary specialisation, in Myzia oblongoguttata. Similar factors to those which bring C. septempunctata into contact with ants were probably of importance in the initial stages of the evolution of myrmecophily of its congener, Coccinella magnifica.
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adaptations of Coccinella magnifica redtenbacher a myrmecophilous coccinellid to aggression by wood ants formica rufa group i adult behavioral adaptation its ecological context and evolution
Journal of Insect Behavior, 1998Co-Authors: John J Sloggett, Richard A Wood, Michael E N MajerusAbstract:Coccinella magnifica is an obligate associate of Formica rufa-group ants. The congener Coccinella septempunctata can serve as a model for its nonmyrmecophilous ancestor. Formica rufa behavior toward these two ladybirds, and their behavior, was compared. Although C. magnifica was rarely attacked on ant trails, it was usually attacked on tended aphid colonies. Coccinella septempunctata was more readily attacked. The two ladybirds' behavior was similar on trails, but C. magnifica used more defense and C. septempunctata more rapid escape behavior on aphid colonies. Only C. magnifica fed upon tended aphids. Chemical adaptation to overcome ant aggression probably exists in C. magnifica, but it possesses almost no novel behaviors to counter ant aggression. Instead, modifications have occurred in the expression of behaviors present in C. septempunctata.
John E Losey - One of the best experts on this subject based on the ideXlab platform.
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egg predation by the introduced lady beetle Coccinella septempunctata coleoptera coccinellidae lowers mortality but raises relative risk for the native lady beetle Coccinella novemnotata
PLOS ONE, 2015Co-Authors: Rakim Turnipseed, Todd A Ugine, John E LoseyAbstract:Populations of the native ninespotted lady beetle, Coccinella novemnotata Herbst, have undergone precipitous declines in North America following the establishment of the exotic sevenspotted lady beetle, Coccinella septempunctata L. Recent volunteer efforts have made it possible to establish colonies of the now-rare C. novemnotata and test mechanisms contributing to its decline. We evaluated the relative frequencies of intraguild predation and cannibalism of eggs between these two species. A single C. novemnotata or C. septempunctata adult was exposed to conspecific and heterospecific eggs in either the presence or absence of pea aphids. The study revealed two expected results: 1) eggs of C. novemnotata were consumed more frequently than eggs of C. septempunctata by both species, and 2) egg consumption was higher when aphids were absent, independent of predator and egg species. There were also two unexpected results from the study: 1) the asymmetry between egg predation rates was higher when aphids were present, and 2) higher predation rates on C. novemnotata eggs in the absence of alternate prey was due to a relatively higher rate of intraspecific cannibalism. This implies that C. novemnotata would have suffered higher egg mortality rates before the invasion of C. septempunctata, but even though the aggregate rate of egg predation on C. novemnotata eggs is lower post-invasion, it is still significantly higher than the aggregate rate of predation of C. septempunctata eggs. This differential pattern of asymmetric predation could contribute to habitat compression and the overall decline of C. novemnotata.
Todd A Ugine - One of the best experts on this subject based on the ideXlab platform.
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interactions of Coccinella novemnotata coleoptera coccinellidae and Coccinella septempunctata coleoptera coccinellidae while foraging for aphids
Environmental Entomology, 2018Co-Authors: Todd A Ugine, Evan Hoki, John E LoseyAbstract:The importation and establishment of Coccinella septempunctata L. (Coleoptera: Coccinellidae) in North America purportedly caused the displacement and local extirpation of the native ninespotted lady beetle, Coccinella novemnotata Herbst (Coleoptera: Coccinellidae), across most of its former range, and several reports have shown that C. septempunctata maintains competitive advantages over C. novemnotata. We investigated the role of aphid density on the retention time of these two species on fava bean plants, and the effect of con- versus heterospecific pairings of adult beetles on the foraging behavior of C. novemnotata. We found that aphid density did not affect C. novemnotata's retention time, but did affect the retention time of C. septempunctata, which left plants without aphids significantly faster than C. novemnotata. Additionally, C. septempunctata females left plants significantly faster than their male counterparts, whereas we observed no difference between the two sexes for C. novemnotata. Our test of pairs of beetles showed that C. novemnotata were together on plants more frequently than conspecific pairs of C. septempunctata and heterospecific pairs of beetles, and that all beetles were more likely to be found together on the aphid-infested plant versus the non-infested plant regardless of the pairs' composition. These results show that C. novemnotata spend more time foraging for aphids when aphids are scarce compared with C. septempunctata, and that C. novemnotata is less tolerant of occupying plants inhabited by C. septempunctata versus a conspecific beetle, adding additional mechanisms whereby C. septempunctata could outcompete C. novemnotata in the field.
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interactions of the asian lady beetle harmonia axyridis coleoptera coccinellidae and the north american native lady beetle Coccinella novemnotata coleoptera coccinellidae prospects for recovery post decline
Environmental Entomology, 2017Co-Authors: Rafael Dal Bosco Ducatti, Todd A Ugine, John E LoseyAbstract:The decline of the North American native lady beetle, Coccinella novemnotata Herbst, is strongly correlated with the introduction of Coccinella septempunctata L., and C. novemnotata are locally extirpated across much of the United States. Since C. novemnotata's decline, the invasive Harmonia axyridis Pallas has become dominant in North America. This study investigated whether H. axyridis has the potential to impede the recovery of C. novemnotata populations. To determine how H. axyridis interacts with C. novemnotata via intraguild predation and competition for prey, we paired first-instar C. novemnotata with first-instar H. axyridis at low and high densities of pea aphid. Coccinella novemnotata survival when paired interspecifically was significantly lower than H. axyridis survival at both aphid densities. Both species had similar weights at eclosion across aphid densities; however, H. axyridis developed faster than C. novemnotata. To examine the effect of larval size on intraguild interactions, we conducted a second experiment where we varied the C. novemnotata and H. axyridis instar in our pairings. Coccinella novemnotata survival and final weight increased when paired with younger H. axyridis larvae. The percentage survival of C. novemnotata in interspecific treatments, at the low aphid density, was lower than for same-aged C. novemnotata reared conspecifically, except for pairs initiated with C. novemnotata larvae that were two instars more advanced than H. axyridis larvae. These results suggest that intraguild predation and competition for prey by H. axyridis have the potential to affect the recovery of C. novemnotata populations negatively.
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egg predation by the introduced lady beetle Coccinella septempunctata coleoptera coccinellidae lowers mortality but raises relative risk for the native lady beetle Coccinella novemnotata
PLOS ONE, 2015Co-Authors: Rakim Turnipseed, Todd A Ugine, John E LoseyAbstract:Populations of the native ninespotted lady beetle, Coccinella novemnotata Herbst, have undergone precipitous declines in North America following the establishment of the exotic sevenspotted lady beetle, Coccinella septempunctata L. Recent volunteer efforts have made it possible to establish colonies of the now-rare C. novemnotata and test mechanisms contributing to its decline. We evaluated the relative frequencies of intraguild predation and cannibalism of eggs between these two species. A single C. novemnotata or C. septempunctata adult was exposed to conspecific and heterospecific eggs in either the presence or absence of pea aphids. The study revealed two expected results: 1) eggs of C. novemnotata were consumed more frequently than eggs of C. septempunctata by both species, and 2) egg consumption was higher when aphids were absent, independent of predator and egg species. There were also two unexpected results from the study: 1) the asymmetry between egg predation rates was higher when aphids were present, and 2) higher predation rates on C. novemnotata eggs in the absence of alternate prey was due to a relatively higher rate of intraspecific cannibalism. This implies that C. novemnotata would have suffered higher egg mortality rates before the invasion of C. septempunctata, but even though the aggregate rate of egg predation on C. novemnotata eggs is lower post-invasion, it is still significantly higher than the aggregate rate of predation of C. septempunctata eggs. This differential pattern of asymmetric predation could contribute to habitat compression and the overall decline of C. novemnotata.
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development times and age specific life table parameters of the native lady beetle species Coccinella novemnotata coleoptera coccinellidae and its invasive congener Coccinella septempunctata coleoptera coccinellidae
Environmental Entomology, 2014Co-Authors: Todd A Ugine, John E LoseyAbstract:To determine if differences in life history parameters contribute to native species exclusion, immature development times, larval survivorship, reproductive life history parameters, and age-specific life tables were determined for two populations (eastern United States and western United States) of ninespotted lady beetles (Coccinella novemnotata Herbst) and one population of sevenspotted lady beetles (Coccinella septempunctata L.). Developing larvae were provided an ad libitum diet of pea aphids (Acyrthosiphon pisum Harris) at a constant temperature of 25°C. The first and fourth larval stadia of C. novemnotata were significantly longer than that of C. septempunctata, as was their total development time from egg to newly eclosed adult. Stage-specific developmental mortality was low for both species and did not exceed 7% for the entire development period. The preoviposition period of the two C. novemnotata populations was significantly shorter (15-20%) than that of C. septempunctata. C. novemnotata from both locations laid significantly fewer total eggs than C. septempunctata (34-40% fewer) over the 31-d test period, and also fewer eggs per day (37-43% fewer). The net reproductive rate of the C. novemnotata populations was 42-50% lower than that of C. septempunctata as was C. novemnotata's intrinsic rate of natural increase (rm: 0.1716 and 0.1840 vs. 0.1959 for western and eastern C. novemnotata and C. septempunctata, respectively).
John E Losey - One of the best experts on this subject based on the ideXlab platform.
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interactions of Coccinella novemnotata coleoptera coccinellidae and Coccinella septempunctata coleoptera coccinellidae while foraging for aphids
Environmental Entomology, 2018Co-Authors: Todd A Ugine, Evan Hoki, John E LoseyAbstract:The importation and establishment of Coccinella septempunctata L. (Coleoptera: Coccinellidae) in North America purportedly caused the displacement and local extirpation of the native ninespotted lady beetle, Coccinella novemnotata Herbst (Coleoptera: Coccinellidae), across most of its former range, and several reports have shown that C. septempunctata maintains competitive advantages over C. novemnotata. We investigated the role of aphid density on the retention time of these two species on fava bean plants, and the effect of con- versus heterospecific pairings of adult beetles on the foraging behavior of C. novemnotata. We found that aphid density did not affect C. novemnotata's retention time, but did affect the retention time of C. septempunctata, which left plants without aphids significantly faster than C. novemnotata. Additionally, C. septempunctata females left plants significantly faster than their male counterparts, whereas we observed no difference between the two sexes for C. novemnotata. Our test of pairs of beetles showed that C. novemnotata were together on plants more frequently than conspecific pairs of C. septempunctata and heterospecific pairs of beetles, and that all beetles were more likely to be found together on the aphid-infested plant versus the non-infested plant regardless of the pairs' composition. These results show that C. novemnotata spend more time foraging for aphids when aphids are scarce compared with C. septempunctata, and that C. novemnotata is less tolerant of occupying plants inhabited by C. septempunctata versus a conspecific beetle, adding additional mechanisms whereby C. septempunctata could outcompete C. novemnotata in the field.
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interactions of the asian lady beetle harmonia axyridis coleoptera coccinellidae and the north american native lady beetle Coccinella novemnotata coleoptera coccinellidae prospects for recovery post decline
Environmental Entomology, 2017Co-Authors: Rafael Dal Bosco Ducatti, Todd A Ugine, John E LoseyAbstract:The decline of the North American native lady beetle, Coccinella novemnotata Herbst, is strongly correlated with the introduction of Coccinella septempunctata L., and C. novemnotata are locally extirpated across much of the United States. Since C. novemnotata's decline, the invasive Harmonia axyridis Pallas has become dominant in North America. This study investigated whether H. axyridis has the potential to impede the recovery of C. novemnotata populations. To determine how H. axyridis interacts with C. novemnotata via intraguild predation and competition for prey, we paired first-instar C. novemnotata with first-instar H. axyridis at low and high densities of pea aphid. Coccinella novemnotata survival when paired interspecifically was significantly lower than H. axyridis survival at both aphid densities. Both species had similar weights at eclosion across aphid densities; however, H. axyridis developed faster than C. novemnotata. To examine the effect of larval size on intraguild interactions, we conducted a second experiment where we varied the C. novemnotata and H. axyridis instar in our pairings. Coccinella novemnotata survival and final weight increased when paired with younger H. axyridis larvae. The percentage survival of C. novemnotata in interspecific treatments, at the low aphid density, was lower than for same-aged C. novemnotata reared conspecifically, except for pairs initiated with C. novemnotata larvae that were two instars more advanced than H. axyridis larvae. These results suggest that intraguild predation and competition for prey by H. axyridis have the potential to affect the recovery of C. novemnotata populations negatively.
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development times and age specific life table parameters of the native lady beetle species Coccinella novemnotata coleoptera coccinellidae and its invasive congener Coccinella septempunctata coleoptera coccinellidae
Environmental Entomology, 2014Co-Authors: Todd A Ugine, John E LoseyAbstract:To determine if differences in life history parameters contribute to native species exclusion, immature development times, larval survivorship, reproductive life history parameters, and age-specific life tables were determined for two populations (eastern United States and western United States) of ninespotted lady beetles (Coccinella novemnotata Herbst) and one population of sevenspotted lady beetles (Coccinella septempunctata L.). Developing larvae were provided an ad libitum diet of pea aphids (Acyrthosiphon pisum Harris) at a constant temperature of 25°C. The first and fourth larval stadia of C. novemnotata were significantly longer than that of C. septempunctata, as was their total development time from egg to newly eclosed adult. Stage-specific developmental mortality was low for both species and did not exceed 7% for the entire development period. The preoviposition period of the two C. novemnotata populations was significantly shorter (15-20%) than that of C. septempunctata. C. novemnotata from both locations laid significantly fewer total eggs than C. septempunctata (34-40% fewer) over the 31-d test period, and also fewer eggs per day (37-43% fewer). The net reproductive rate of the C. novemnotata populations was 42-50% lower than that of C. septempunctata as was C. novemnotata's intrinsic rate of natural increase (rm: 0.1716 and 0.1840 vs. 0.1959 for western and eastern C. novemnotata and C. septempunctata, respectively).
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sexual dimorphism in north american coccinellids sexing methods for species of Coccinella l coleoptera coccinellidae and implications for conservation research
Coleopterists Bulletin, 2014Co-Authors: Leo Stellwag, John E LoseyAbstract:Abstract Coccinellids typically do not show exaggerated sexual dimorphisms, and the only reliable sexing methods for some species have been dissection and behavioral observations. Behavioral methods can potentially lead to sex identification but are very time consuming, require exposing sexually naive individuals to conspecifics, and risk incorrect identification since homosexual mounting in these species has been observed in the laboratory. Research involving use of live specimens requires techniques to non-invasively determine the sex of individuals, but such methods have not been clearly or fully described in the literature. Closer examination of the species Coccinella novemnotata Herbst, Coccinella septempunctata L., Coccinella transversoguttata richardsoni Brown, and Coccinella trifasciata perplexa Mulsant has led to the discovery of a reliable and efficient way to differentiate the sexes by looking at the shape of the seventh sternite (fifth visible), and this method has been demonstrated to be 100%...
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recent records of adalia bipunctata l Coccinella transversoguttata richardsoni brown and Coccinella novemnotata herbst coleoptera coccinellidae from south dakota and nebraska
Coleopterists Bulletin, 2009Co-Authors: Louis S Hesler, Michael A Catangui, John E Losey, J B Helbig, A MesmanAbstract:Abstract Adalia bipunctata (L.), Coccinella transversoguttata richardsoni Brown, and C. novemnotata Herbst (Coleoptera: Coccinellidae) were previously common throughout much of North America, but their numbers have declined drastically over the last few decades. This paper reports on recent findings of these species at nine sites in western South Dakota and western Nebraska in 2008. Nine A. bipunctata, 11 C. transversoguttata richardsoni, and 12 C. novemnotata were among 930 coccinellids sampled overall. An additional C. transversoguttata richardsoni was among coccinellids captured on a sticky trap in a wheat field during survey for cereal leaf beetle, Oulema melanopus (L.), in Butte, County, South Dakota in 2000. In several instances, adult C. transversoguttata richardsoni and C. novemnotata were observed on plants with other coccinellids, especially Hippodamia convergens Guerin-Meneville, a native species, and Coccinella septempunctata L., a non-native species. Coccinella septempunctata was observed fee...