A team of scientists from the University of Navarra and the Catalan Association of Biospeleology have discovered three new collembolan species in the Maestrazgo caves in Teruel, Spain. Their description has been published in the Zootaxa journal. These minute animals belong to one of the most ancient animal species on the planet. The Maestrazgo caves in Teruel are located in a region of the Iberian Range where fauna（动物群） has not been the subject of much study. It is a very isolated region since its average altitude is between 1,550 m and 2,000 m asl and its climate can be described as "almost extreme" experiencing temperatures of between -40°C and -25°C. Inside the caves, however, the temperatures remain constant at between 5°C and 11°C.

"Studying fauna in the caves allows us to expand on our knowledge of biodiversity. In the case of the three new collembolan species that we have found in Teruel, they are organisms that have survived totally isolated for thousands of years. Having 'relatives' on the surface means they act like relics from the past that have survived the climate change taken place on the outside of the caves," as explained by Enrique Baquero, who carried out a taxonomic study along with Rafael Jordana, both of whom are from the University of Navarra.

For these scientists it is vital to study how new species found adapt to the cave environments. "Like other cave-adapted animals, the collembolans require greater chemical sensitivity as they cannot use their sight in the absence of light," explains Baquero.

These animals are arthropods（节肢动物） from the hexapod group (meaning six legs), a parallel group to insects. However, they are different and more primitive, showing absence of wings, different structure of their mouth, presence of the ventral organ and frequently, presence of the springing organ named the furca (an uneven abdomen appendix used to jump far away from danger).