Despite its inhospitable appearance and lack of any ... - Udine Cultura

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70 Olm (Proteus anguinus) discovered (Proteus anguinus parkelj) genetically similar to the stygobiont populations of the same area, and thus suggesting that groundwater populations are more recent. Recent molecular analyses reveal that there may be more stygobiont olm species. In Italy, olms are known to inhabit only alkaline water in caves of the Trieste and Isonzo Karsts. An isolated population, introduced from Slovenia in 1850, still lives in Grotta Parolini at Oliero (Vicenza). Olms are the only Italian stygobionts listed as priority species in the Habitats Directive; they are also included in Annex IV and are therefore under strict protection. ■ Italian stygofaunal provinces Some olm specimens, coming from Slovenia, were introduced into the Oliero cave system (Veneto) in 1850 As analysis of previously described taxonomic groups suggests, the present geographical distribution of stygobiont species in Italy is the result of a series of events which took place in ancient times (historical factors) and, to a lesser extent, of ecological factors, which occour in “real time”. The role played by both is described in the chapter on ecology. Since the evolution of many Italian taxonomic groups was similar over time, because they were affected by the same palaeogeographical events, Italy is divided into areas with similar fauna, particularly endemics. These areas are called stygofaunal provinces. Although these generalisations cannot tell us directly what the present fauna composition of a specific aquifer is, because this is also influenced by local events, they do describe the present situation of Italian stygobionts and explain where the most important endemic locations are found. Dinaric province. This area includes only the easternmost portion of Italy - the so-called “classic” Karst - an elliptical area of 200 km 2 , whose stygobionts are similar to those of the Karst in Slovenia, Istria and Dalmatia. 71
72 Stygofaunal provinces in Italy The area was affected by karstification in the late Miocene, and hosts many palaeo-endemics. Exclusive to the karstic vadose zone are harpacticoid copepods of the genus Morariopsis, the bathynellacean Bathynella skopljensis and the amphipod Niphargus stygius. Exceptional fauna, whose western limit of distribution is the Karst, populates large cavities filled with alkaline karstic water. Among these, there are polychaetes (Marifugia cavatica), gastropods (Belgrandia stochi), ostracods (Cypria cavernae), calanoids (Troglodiaptomus sketi), and several cyclopoids and Sphaeromides virei (ca. 1x) harpacticoids (like Acanthocyclops troglophilus and Nitocrella stochi). This area hosts the only Italian stygobiont isopods of the genus Asellus, those of the subgenus Microlistra, and the large Sphaeromides, as well as amphipods, which are highly diversified, with many endemics (e.g., Niphargus stochi, Hadzia fragilis). Other remarkable inhabitants are decapods of the genus Troglocaris, and the most famous stygobiont species, the olm (Proteus anguinus). Aquifers in marl and sandstone also host very interesting fauna, with very different species from those found in adjacent karstic aquifers. Among the main biogeographical markers, there is the gastropod Istriana mirnae, and the large amphipods Niphargus spinulifemur and N. krameri. Alpine province. The Alpine stygofaunal province includes a very complex area associated with Alpine orogenetic events. It is divided into a northern part (strictly Alpine), above the southern limit of the great Quaternary glaciations, and a southern Pre-Alpine one, below which is the recent alluvial area of the Po Plain. The Alpine area is populated by only a few stygobionts: cold-loving, stenothermal species which followed the retreat of Quaternary glaciers and colonised aquifers in carbonate and crystalline rocks in the Alps. In particular, a number of amphipods (Niphargus forelii, N. similis, N. strouhali) even live at high altitudes, above 2000 m, together with a few copepods and bathynellaceans. 73
Page 1 and 2: Fauna FABIO STOCH Despite its inhos
Page 3 and 4: 44 45 Methods for sampling and anal
Page 5 and 6: 48 Shells of gastropods Iglica voba
Page 7 and 8: 52 collected in phreatic waters in
Page 9 and 10: 56 ● Cyclopoid copepods. So far,
Page 11 and 12: 60 those associated with percolatin
Page 13 and 14: 64 Species of genus Niphargus; top:
Page 15: 68 ■ Decapods Italian fauna has o
Page 19 and 20: 76 aquifers in the Sabini mountains
Page 21 and 22: 80 ■ The ecology of aquifers Acco
Page 23 and 24: 84 85 The discovery of a new submer
Page 25 and 26: 88 anastomoses, often adjacent to t
Page 27 and 28: 92 93 The saline springs of Poiano:
Page 29 and 30: 96 Modified sensory setae on the an
Page 31 and 32: 100 Theoretical evolutionary sequen
Page 33 and 34: 104 Sketch showing degrading phases
Page 35 and 36: 108 109 Stygodiversity in the Presc
Page 37: 112 animal groups still living on t

Despite its inhospitable appearance and lack of any ... - Udine Cultura

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