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A bite from a funnel web spider delivers neurotoxins that can kill an adult in hours, or a child in minutes. Their fangs are so sharp and powerful that they can pierce fingernails. Yet they might turn out to be our friends in the fight against the small hive beetle, a dangerous new threat to bees.

In southern Africa, where it originates, the small hive beetle 鈥� Aethina tumida 鈥� is just a minor pest. African honeybees defend their nests so aggressively, and keep them so tidy, that the invader rarely gets a foothold. Outside Africa, however, nests of the more laidback European honeybee (Apis mellifera) are often devastated by the beetle and its larvae, which devour the honey, pollen and brood, destroy the combs and sometimes introduce diseases.

A. tumida was first found in the US in 1998, and has since established itself in North America and Australia, and begun to appear in southern Europe. Some pesticides can kill the beetles, but in doing so they would harm the bees as well.

Now researchers at the University of Durham and at a company called Fera Science, both in the UK, think that funnel web spiders may provide the weapon we need to stop A. tumida. Spider venom contains a cocktail of different ingredients, and we鈥檝e known for a while that one of the funnel web鈥檚 toxins 鈥� Hv1a 鈥� is fatal to most insects, including small hive beetles, but apparently has no effect on bees or humans. The trouble was that Hv1a needs to be injected.

Flower power

鈥淲hen the spider makes an injection it goes straight to the circulatory system, then to the central nervous system,鈥� says Elaine Fitches, whose team conducted the research. If beetles or their larvae simply swallow the toxin, it quickly degrades in the gut and has little effect.

Fitches and her team appear to have solved the problem, however, by binding Hv1a to another molecule found in the common snowdrop, Galanthus nivalis, which effectively carries it through the gut barrier. In the lab, they fed the 鈥渇usion protein鈥� in a sugar solution to beetles and their larvae.

After two days the larvae started 鈥渨rithing鈥�. Within a week, both larvae and adults were all dead. They also placed beetle eggs on a piece of honeycomb containing bee brood, which was then sprayed with the new compound. The honeycomb and bees survived virtually untouched, and most of the new beetle larvae died. Even when honeybees were anaesthetised and delicately injected with the fusion protein, at least 90% survived.

Research is at an early stage, but it is possible that a whole range of biopesticides could eventually emerge from spider venom, by binding different toxins to other proteins in a similar way. 鈥淚 was absolutely chuffed to bits with these results,鈥� Fitches says.