With their powerful stingers and scissors, scorpions penetrate even the tough shells of their victims and enemies. A study now shows how they specifically reinforce their weapons with stored metals. Zinc, manganese and iron are used primarily at the tip of the stinger and on the cutting edges of the scissors to make the weapons sharper and more durable. How exactly the metals are distributed depends on the respective species and its specific strategies for hunting and defense.
Scorpions use their pincers and stingers to defend themselves against attackers and to overwhelm their prey. How much they rely on which type of weapon varies from species to species. Some scorpions prefer to use their pincers and only sting when the prey is difficult to overpower, while others use their stingers more aggressively. Some have oversized, powerful claws but relatively small spines, while others have the opposite. Since most species feed primarily on other arthropods whose bodies are protected by a hard exoskeleton, the scorpions’ weapons must be so strong that they can penetrate even hard armor if necessary.
Targeted reinforcement
“Scorpions are incredible hunters, and although we knew that metals strengthen the weapons of some species, it was unclear whether the weapons of all scorpions contain metal, and if so, whether this metal accumulation was related to their hunting style,” says Sam Campbell of the University of Queensland in Australia. To answer these questions, Campbell and his team examined the weapons of 18 species from different scorpion families using electron microscopy and X-ray structural analysis.
The researchers discovered that the metals were not evenly distributed in the scissors and spines. Instead, they are used specifically in the most important places. In the stinger, zinc reinforces the outermost tip and enables a structure that is as fine as a needle and yet so stable that it does not break off at the first contact with an enemy. Immediately below, manganese becomes the dominant metal and provides additional stability. A similar pattern can be seen with the scissors. Here the metals are found almost exclusively along the cutting edge and thus specifically reinforce the parts that are exposed to the greatest stress when catching prey. Zinc or a combination of zinc and iron are most common here.
Differences depending on hunting strategy
The analysis also revealed significant differences between different species. Scorpions, who rely primarily on their stingers, reinforce this with metals. Scorpions, on the other hand, who primarily use their scissors for hunting and defense, store most of their metals here and save on their stingers. “The diversity and specificity of metal accumulation in the scorpion species studied here reflect the different roles that these specialized weapons play in different genera,” explains the research team.
Source: Sam Campbell (University of Queensland, Brisbane, Australia) et al., Journal of The Royal Society Interface, doi: 10.1098/rsif.2025.0523