The survival of particular ecosystems such as woods, wetlands, springs and different subterranean environments mainly depends on their biodiversity, variety of plants, animals, and habitats, as well as the many interactions among the species: the removal, reduction or disappearance of one or more animal or vegetal species may irreversibly damage the natural ecosystems leading to their progressive decline.

At present most human activities tend to change the ecological stability or promote fragmentation of natural and often species-rich environments, this proceeding particularly involving small, isolated populations which are more sensitive than larger connected ones to demographic or environmental factors. The risks of this kind of distribution patterns may be compounded by other external threats, such as excess exploitation, introduced predators, pollution or stochastic events whose impact could be increased by human activities.

Groundwater environments are precious resources for a number of vital functions, such as economical, industrial and agricultural water supply, and about 80% of the World inhabitants are dependent on this resource for their water different supplies. Subterranean aquifers are stored as large reservoirs in the porous underground: the vital function of these reservoirs are at present time strongly threatened by the effects of pollution and overexploitation. Ground waters are not only reservoirs but also ecological systems: they are inhabitated, along with microorganisms and protozoans, by a rich and diverse fauna, which cooperate in keeping the groundwater bearing strata clean of organic particles entering the groundwater from the soil or surface waters.

Groundwater quality of many european countries, Italy included, is at present affected by intrusive use of chemical substances, pesticides and fertilizers, garden chemicals, accidental or intentional dumping of toxic substances, sewage contamination and absorption from septic tanks, land application of hazardous waste or illegal species collecting. Many cave or subterranean freshwater aquatic species (eg. fishes, amphibians and most crustaceans) have very restricted ranges, perhaps consisting of a single cave or aquifer, and very limited opportunities for dispersal, depending on the surrounding geomorphology and the relative morphology of the water system occupied: consequently, they are strongly affected by even moderate environmental changes or pollution, in some cases, the longitudinal distribution of several interstitial (hyporheic) species is highly affected by the distance to water discharge, as well as low or medium concentration of nitrite, nitrate, sulphate and ammonia.

Because of the extreme isolation, uniqueness and hard conditions of the groundwater environments, animals living in subterranean habitats of Italy, especially stygobitic specialists, are rare, in most cases they are endemic or restricted to very small areas. Most species are believed to be threatened primarly by degraded groundwater quality as a result of different sources such as application of agricultural and residential pesticides, fertilizers in subterranean streams or caves recharge areas, and contamination from human and animal waste, and they merit threatened or endangered status at different levels.

The more worrisome situations are in both inland and costal (anchialine) caves and phreatic environments. At present, notwithstanding WWF-Italy, Bioitaly, APE (Appennino Parco d'Europa), and other governative or private istitutions are actively promoting interventions to catalogue and protect the natural environments of Italy, the subterranean aquifers of this country are not holded in due consideration, and their groundwater biota are still greatly endangered, most species being threatened as well as they are facing an extremely high risk of extintion in the immediate future!

Most endangered italian areas are the Po, Arno and Tevere hyporheic basins, the north-east karst region, and the karst aquifers of south Italy (Salentine Peninsula), Sicily and Sardinia. In the above areas numerous karst ecosystems, phreatic habitats, springs and caves, such as “Buso della rana” (Vicenza, north Italy), Mugnone river basin (Tuscany), Pescara springs (L’Aquila, central Italy), “Grotte di Stiffe” (L’Aquila, central Italy), “Grotta dell’Arco” (Rome, central Italy), Grotta di Pertosa” and “Grotta di Castelcivita” (Salerno, south Italy), “Grotta di S. Pietro”, “Grotta di Nettuno” and “Grotta su Coloru” (Sardinia), anchyaline systems of Porto Palo (Sicily) and the Zinzulusa, Buca dei Diavoli and L’Abisso caves (south Italy) are variously threatened by turism, agriculture and urbanization, nearness of hydro-electric reservoirs, as well as invasion of alien species and carelessness cavers who often are aware of the presence of rare, often single species, in the above environments. Locally, as in central Apennines, the tunnels recently escavated under the “Gran Sasso” mountain, are determining the sinking of a rich phreatic network and, as a consequence, the impoverishment of the surrounding small springs and their remarkable fauna, which include several rare and endemic species.

As a proof of the present high threatening of the italian subterranean ecosystems, the Zinzulusa cave has been recently included in the “Ten Most Endangered Karst Communities for 1999“ by the Karst Water Institute since, notwhistanding it probably arbors the most diverse and rich cave animal fauna in Europe (more than 50 stygobitic or stygophilic taxa, most endemic and of ancient lineage), is at present strongly polluted from urban discharge, waters threatens the cave as do tourists who litter and destroy natural formations mainly near the entrance of the cave. The fauna of this remarkable cave, which could be considered a remarkable biodiversity “hot spot”, is certainly vulnerable and protection requires habitat preservation as well as conservation of the associate epigean habitat.

Unfortunately, most suberranean fauna is not taken in account in the existing european and italian protection laws, as well as the relative “Red Lists” are not updated and in strong need of revision. At present only France and Spain, following the Recommendation n. 36 (1992) on the conservation of the underground habitat from the Council of Europe, are actively engaged in the conservation of the underground habitat, a project of natural Reserve for conservation of all habitat types and all red list species present in Spain and a French Pyrenean department (Ariege) is in route by the French "Ministere de l'Environnement".

At present time 60 groundwater (caves and phreatic habitats) inhabitant species, all crustaceans, could be classified as variously threatened or endangered in Italy, and among these most are stygobitic specialists or eustygophilic taxa, of remarkable scientific interest, and belonging to different IUCN categories (VU D1 D2, EW; EN A2 B1 C2, CR Ae, LR1 LR2); most of them, on account of the restriction of their area or the few known localities, fit the Red List category VU D.

The copepods are the most numerous; of the more than 150 subterranean species and subspecies presently known from Italy, only 37 are classified as threatened in that country. Most of these are stygobitic or eustygophilic taxa, of remarkable scientific interest, and belong to different IUCN categories; most of them, on account of the restriction of their area or the few known localities, fit the Red List category VU D (Vulnerable, restricted area).

But this number is certainly a minimum estimate , since more taxa could be added to the list in the categories "Data deficient" or "Near Threatened", since there are no adequate data to assess their risk of extintion, or they do not qualify as conservation-dependent, but are close to qualifying as vulnerable.

Therefore, it is imperative to know the present status of these taxa , obtain more information to determine their appropriate listing, and to implement necessary and opportune studies. But the above number is surely underestimated since more, also non-crustacean, taxa could be added to the list in the categories “Data deficient” (DD) or “Near Threatened” (NT), as well as in other categories, since at present time there are no adequate data to make an assessment of their risk of extintion, or they do not qualify for conservation dependent, but are close to qualifying for vulnerable. Therefore, it is imperative to know the updated conditions of all the above taxa, as well as to taken necessary and opportune measures in order to stop and reverse their negative trend.