Most scorpions on Earth are ready to sting but hold back. What are they waiting for? (photo)

Scorpions are arachnids widely recognized for their stingers. Science has identified over 2,500 species that utilize their appearance to subdue prey and defend against predators. The tails of scorpions end in a structure known as the telson, which contains a bulb filled with venom. This structure is typically equipped with a pointed stinger, which is used to inject the venom. However, there is another method, reports Live Science.

In a recent study, scientists discovered and described a new species of scorpion named Tityus achilles. This species was found in the mountainous region of tropical forests in Magdalena, Colombia. The most intriguing aspect of this discovery is that the new species can both spray and inject its venom—previously thought to be a capability exclusive to only two other genera residing in Africa and North America.

According to the study's author, Leo Laborie from Ludwig Maximilian University of Munich, most scorpions in the world are likely capable of spraying their venom but do not do so. This extreme behavioral response is known to occur regularly in only two genera of animals.

The reason is that spraying venom is inherently a costly strategy. Scientists believe there is strong selection pressure that makes this behavior more advantageous than disadvantageous. In simple terms, something must occur with predators in the environment that prompts them to take this risky step.

The study authors found that the new species is capable of both injecting and spraying its venom. Direct injection guarantees delivery and impact on the target; however, there are risks involved—prey may resist. Spraying venom is less risky and does not require direct physical contact, but it is less precise, and the consequences for the prey or predator are less severe. Still, the streams of toxin may be sufficient to deter a predator and give the scorpion time to escape.

According to Laborie, the angle of the scorpion's toxin spray suggests it can be directed towards the nose or eyes. Researchers believe that the venom must reach very sensitive tissues to be truly effective. It is also thought that the venom is aimed at vertebrates since toxins are unlikely to penetrate an exoskeleton.

During the study, the team tested the scorpions' ability to spray venom. The animals were prodded with a straw, and their reactions were recorded. A total of 10 juvenile specimens were tested, resulting in 46 venom expulsions—the maximum distance achieved was 36 centimeters.

In some instances, scorpions ejected small droplets of venom in response to the straw. In other cases, they released a continuous stream. Most venom impulses were directed forward, although some were also aimed backward or upward.

The study authors also discovered that most of the venom expulsions were clear. In simple terms, they likely represented pre-venom—a toxic liquid typically expelled before a strong, true venom that has a milky appearance.