The evolutionary history of the scorpions begun around 425 – 450 million years ago, in the middle Silurian. More than 1500 species have been recognized and classified in different families. Mesobuthus cyprius, one of the two endemic scorpions in Cyprus, belongs in the family of Buthidae which is geographically distributed worldwide and is the largest of the scorpion families. Moreover, from a clinical perspective, Buthidae is the most important scorpion family as several members of this family are toxic to mammals and can be dangerous to humans. Even though Mesobuthus cyprius was discovered in 2000 using molecular phylogenetics there are no other published data regarding the peptide and protein composition, the toxicity, or any other activity of the venom.

For this research work, several specimens were collected, and their venom composition was studied using Liquid Chromatography tandem Mass Spectrometry techniques (LC-PDA-MS and UPLC-TOF-MS). Furthermore, the comparison of the venom of Mesobuthus Cyprius with the venom of Mesobuthus gibbosus was performed, the closest member of the family, common in Greece and Turkey. The same venoms were studied with solution state Nuclear Magnetic Resonance Spectroscopy (NMR). Finally, we tested the venom for its ability to cause cell death in a number of cancer cell lines.