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Start Over Creator Sloggett, John J.

1. Adaptations of Coccinella magnifica, a myrmecophilous coccinellid to aggression by wood ants (Formica rufa group). II.. Larval behaviour, and ladybird oviposition location1

Creator:
Sloggett, John J. and Majerus, Michael E.N.
Type:
article, model:article, and TEXT
Subject:
occinella magnifica, Coccinella septempunctata, Formica rufa, ant-tended aphids, myrmecophily, and oviposition
Language:
English
Description:
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.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

2. The ant-associations and diet of the ladybird Coccinella magnifica (Coleoptera: Coccinellidae)

Creator:
Sloggett, John J., Völkl, Wolfgang, Schulze, Werner, Schulenburg, Hinrich G.V.D., and Majerus , Michael E.N.
Type:
article, model:article, and TEXT
Subject:
Coccinella magnifica, myrmecophily, Formica rufa group, habitat preference, aphidophagy, geographic variation, and Coccinella septempunctata
Language:
English
Description:
The ladybird Coccinella magnifica is typically considered to be myrmecophilous, and primarily associated with the Formica rufa group of wood ants. It is regularly associated with ants of the F. rufa group in north-western Europe. The very limited data on the habitat preference of C. magnifica in the southern and eastern parts of its range indicate that its ant-associations change and that it may even be non-myrmecophilous in this region. C. magnifica might consist of geographically restricted species or semispecies, on the basis of its geographical variation in ant-association. Laboratory and field observations on north-western myrmecophilous populations C. magnifica appear to indicate it is a generalist predator of aphids. Coccinella magnifica's potential dietary breadth is similar to that of its congener Coccinella septempunctata, which has been used as a model of C. magnifica's non-myrmecophilous ancestor in evolutionary studies.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

3. Weighty matters: Body size, diet and specialization in aphidophagous ladybird beetles (Coleoptera: Coccinellidae)

Creator:
Sloggett, John J.
Type:
article, model:article, and TEXT
Subject:
Body size, prey size, prey density, capture efficiency, dietary breadth, specialization, Coccinellidae, and aphids
Language:
English
Description:
Aphidophagous ladybirds exhibit a broad range of body sizes. Until now this has been thought to be a function of the different prey densities that they feed at, with smaller ladybirds feeding at lower prey densities. The size of the prey species they feed on has been considered to have no relationship with ladybird body size. However, these arguments possess a limited capacity to explain observed data from the field. I here demonstrate a more realistic, complex approach incorporating both prey density and the size of prey species. Small ladybirds can feed on small aphids at both low and high densities. However when the aphid species is large they cannot catch the older, bigger, more energy-rich aphid instars due to their small size. They are thus unable to feed on large aphid prey at low densities, although at higher densities numbers of the smaller instars may be sufficient to sustain them. By contrast large ladybirds can feed on large aphids at both low and high densities due to their superior ability to catch the bigger, more energy-rich older aphids; however they cannot be sustained by low densities of small aphids due to food limitation consequent on their large size. This more complex association between ladybird size, prey size and prey density possesses a better explanatory power for earlier field data. Because of this relationship, ladybird body size also provides an important trade-off determining dietary breadth and specialization in the aphidophagous Coccinellidae. Dietary specialists more closely match the size of their limited prey species, have higher overall capture efficiencies and can thus continue to reproduce at lower aphid densities for longer. By contrast dietary generalists adopt a one-size-fits-all strategy, are medium-sized and have lower capture efficiencies of individual prey species, thus requiring higher aphid densities. The role of body-size in dietary specialization is supported by data from the British fauna. Rather than trade-offs related to prey chemistry, which have hitherto been the centre of attention, body size trade-offs are the likely most important universal factor underlying dietary specialization in aphidophagous coccinellids.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public