Scorpion Venom “Fingerprints” May Help Find Hidden Species

Scorpion venom is more than a weapon. It may also hold clues to the identity of the animal that produces it, offering a new tool for biodiversity research and species classification.

In a new study in the journal Toxicon: X, researchers from the Museum, the University of Lisbon, and the University of Cologne compared, for the first time, the ability of venom “fingerprints” to traditional approaches for identifying and distinguishing scorpion species.

Adult males of nine Italian scorpion species sampled for the study: A. Euscorpius concinnus. B. Euscorpius latinus. C. Euscorpius trejaensis. D. Euscorpius celanus. E. Euscorpius garganicus. F. Euscorpius salentinus. G. Euscorpius aquilejensis. H. Euscorpius italicus. I. Tetratrichobothrius flavicaudis.
© Massimiliano Roppo

“Scorpion venom is a complex mixture of hundreds of different molecules, including proteins, peptides, and enzymes,” said the study’s lead author Javier Blasco-Aróstegui, a visiting scientist at the Museum and a Ph.D. student at the University of Lisbon. “Although the venom of individuals from the same species can vary, some of these molecules appear to be characteristic of particular species. This means that venom can contain a kind of chemical fingerprint that helps us recognize one species from another. But we wanted to know: can we distinguish among species of scorpions based only on their venom fingerprint?”

To explore this question, the researchers examined venom from eight species of Euscorpius scorpions from Italy. Using a technique called mass spectrometry, they analyzed the molecular composition of venom, which resulted in distinctive patterns much like chemical barcodes. Researchers then compared these patterns with DNA sequence data to test how reliably venom fingerprints could distinguish species.

The study’s lead author Javier Blasco-Aróstegui extracting venom from a Euscorpius specimen in the field in Italy.
© Javier Blasco-Aróstegui

The results were encouraging. Venom fingerprints differentiated both closely related and more distantly related species, distinguishing groups that largely matched those identified through DNA sequence analysis. This is particularly important for identifying cryptic species, species that are distinct but look so similar that examining physical traits alone may fail to tell them apart.

However, the study also revealed an important limitation: although venom fingerprints were effective at distinguishing species, they were less reliable than DNA for reconstructing deeper evolutionary relationships. Venom chemistry can evolve rapidly and is influenced by biological and ecological factors, so it may provide a less reliable picture of evolutionary history.

“Overall, we show that venom can complement, rather than replace, DNA and morphology,” said Museum Curator Lorenzo Prendini, who participated in the study. “By combining genetic, anatomical, and chemical evidence, researchers can build a more complete and reliable understanding of scorpion diversity, potentially uncovering species that might otherwise remain hidden.”

The next step is to test this approach across more scorpion species and geographical regions, while developing automated methods to analyze venom profiles more quickly and consistently.

Beyond taxonomy, a better understanding of scorpion venom diversity could also support research into medically important species and help researchers investigate venom molecules with potential pharmacological applications.