Zur Regelung der Stellung des femur-Tibia-Gelenkes im Mesothorax der Wanderheuschrecke Schistocerca gregaria (Forsk�l)

The toxicities of sprays of some insecticides used against locusts have been determined. The LD50's of γ BHC, diazinon, and dieldrin to both flying and settled adults of Schistocerca gregaria (Forsk.) were between 0·9 and 1·5 times those of the same formulations when applied as a single drop to the abdomen. The toxicity of these insecticides was not affected by the size of the spray droplets when these ranged from about 60 to 250 µ in diameter. The toxicity of DNC, however, was always less by spray application than when applied by micro-drop syringe and was affected by the droplet diameter (droplets of 100 µ being 1·5 times as toxic as those of 200–230 µ) and by whether the locusts were sprayed in flight or when tethered on a card (those in flight being about 1·6 times as susceptible to 100 µ droplets as those at rest). A tentative explanation of this effect is given.The speed of action of the insecticides was compared and the effects of flight activity on susceptibility to the insecticides when sprayed over the flying insects was examined, but none could be detected by the technique used.

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Infection of Schistocerca gregaria by the fungus Metarhizium anisopliae: Cellular reactions in the integument studied by scanning electron and light microscopy

Journal of Invertebrate Pathology ◽

10.1016/0022-2011(88)90096-1 ◽

1988 ◽

Vol 52 (1) ◽

pp. 9-17 ◽

Cited By ~ 34

Author(s):

S.G.S. Gunnarsson

Keyword(s):

Light Microscopy ◽

Metarhizium Anisopliae ◽

Schistocerca Gregaria ◽

Electron And Light Microscopy ◽

Scanning Electron

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Strength of forelimb lateralization predicts motor errors in an insect

Biology Letters ◽

10.1098/rsbl.2016.0547 ◽

2016 ◽

Vol 12 (9) ◽

pp. 20160547 ◽

Cited By ~ 26

Author(s):

Adrian T. A. Bell ◽

Jeremy E. Niven

Keyword(s):

Motor Control ◽

Schistocerca Gregaria ◽

Individual Level ◽

Gap Crossing

Lateralized behaviours are widespread in both vertebrates and invertebrates, suggesting that lateralization is advantageous. Yet evidence demonstrating proximate or ultimate advantages remains scarce, particularly in invertebrates or in species with individual-level lateralization. Desert locusts ( Schistocerca gregaria ) are biased in the forelimb they use to perform targeted reaching across a gap. The forelimb and strength of this bias differed among individuals, indicative of individual-level lateralization. Here we show that strongly biased locusts perform better during gap-crossing, making fewer errors with their preferred forelimb. The number of targeting errors locusts make negatively correlates with the strength of forelimb lateralization. This provides evidence that stronger lateralization confers an advantage in terms of improved motor control in an invertebrate with individual-level lateralization.

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