The olm, often known as the "human fish," has a depigmented body, short limbs, and lives mostly in caves, making it one of the world's most recognizable cave-dwelling animals. It lives in the Dinaric Karst's rivers and underground lakes, which stretch over Bosnia and Herzegovina, Croatia, Italy, and Slovenia, and is recognized for its unusual lifespan, which can last over a century. Despite over 350 years of scientific research and multiple evidence of major differences between populations, the olm has historically been classified as a single species, Proteus anguinus, with the exception of a dark variety discovered in a Slovenian karst spring. Currently, an international team of researchers, including Christophe Dufresnes, a herpetologist at the Musée National d'Histoire Naturelle in Paris, Raoul Manenti, a professor at the Department of Environmental Sciences and Policy, and Benedetta Barzaghi, a researcher and speleologist at the University of Milan, has compiled and compared the available data on the evolution, genetic and physical characteristics, geographic distribution, and habitats of various Proteus populations. The team has also reconstructed the history of their scientific classification. This study, published in the journal Amphibia-Reptilia, found that populations previously thought to be the same species demonstrate enough differences to be identified as nine separate species, three of which are described and named for the first time. Particularly significant is the recognition of the Italian population, which lives in the Classical Karst, as a species in its own right. The new species, described by researchers at the University of Milan, has been called Proteus maurii in honor of naturalist Edgardo Mauri, who has long been committed to the study and conservation of the olm. This discovery emphasizes not just the great evolutionary diversity of European amphibians, but also the vulnerability of the identified species: all occupy small areas, and some are limited to specific groundwater systems.