Observations on the habitat and feeding behaviour of the hypogean genus Eukoenenia (Palpigradi, Eukoeneniidae) in the Western Italian Alps

The order Palpigradi includes species characterized by millimetric size and a characteristic flagellum with bristles at the end of the opisthosoma. They represent one of the less well-known and obscure arachnidorders. In this paper, observations were made on the ecology and feeding behavior of species belonging tothe genus Eukoenenia Börner, 1901, from the Western Italian Alps. Direct observations and photographicdocumentation of 141 individuals in their cave habitat, allowed the recording of data on the physical andtrophic conditions such as the presence/absence of trophic resources, temperature and relative humidity,of the underground environment in which they were found. Results showed that the species of thistaxon are not as rare as previously reported and that their presence is mainly influenced by temperature,relative humidity, trophic resources and the presence of two speleothems: rimstone dams and rafts. Thecombination of our observations as well as data previously published highlights that the taxon can havepredatory and saprophagous feeding behavior depending on the availability of the food resources. Thiswork represents the starting point for a further investigation of the taxon