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

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62 species. Other species are only known to live in restricted areas, like P. amiterninus, P. dianae, P. adriaticus and P. faesolanus. The similar genus Chthonasellus includes C. bodoni, endemic to karstic and interstitial waters in the Cuneo area (Piedmont), which is thought to be phylogenetically close to the French genus Gallasellus. Stenasellids. This family comprises exclusively stygobiont species of very ancient origin, found in Tuscany (Stenasellus gr. racovitzai) and Sardinia, in both caves and interstitial habitats. In Sardinia, techniques of molecular biology have identified many endemics, two of which have so far been attributed to S. racovitzai and are similar to French species, and two others (S. nuragicus, S. assorgiai) are similar to species found in eastern Europe. Two species collected in the area of Nuoro (Sardinia) are similar to Spanish species. Preliminary dating based on “molecular clocks”, suggests that the separation of the two phyletic lines dates back about 28 million years (Upper Miocene). This is one of the most fascinating biological pieces of evidence of the complex Tyrrhenid history. Microparasellids. This family of tiny isopods (a few mm long) deriving from ancient marine ancestors which colonised interstitial habitats during the marine regressive phases. Their distribution follows the ancient coastline of Tertiary seas. In Italy, six interstitial species are known, all belonging to the genus Microcharon (see drawing). Of these, only M. marinus is associated with transient groundwater along the Mediterranean coasts, and the geographical location of other species - e.g. M. novariensis, found in Piedmont springs - reveals that they are relicts. Microcerberids. The family comprises mainly marine species, and only the relict Microcerberus ruffoi (see drawing) lives in Italian underground freshwater (water-table of the river Adige). Cirolanids. This family includes mainly marine species, and only two are Italian stygobionts. Sphaeromides virei inhabits alkaline water in the Gorizia Karst. A voracious predator, it is quite large (more than 3 cm long). Its typically Balkanic distribution and fragmentation into endemic subspecies suggest that it originally lived in groundwater in the Dinaric karst. Typhlocirolana aff. moraguesi is exclusive to the karstic system near Porto Palo (Siracusa, Sicily), and was distinguished from T. moraguesi (island of Majorca) with molecular biology techniques. Its origin is probably palaeo- Mediterranean. Sphaeromatids. Many species of the genus Monolistra, widely distributed in the Balkans, also live between the Italian-Slovenian border and the area of Como (north of Milan), in karstic groundwater in Pre-Alpine caves. Their absence north of the line that marked the southern boundary of the great Quaternary glaciers shows that they settled in groundwater during the Pliocene, perhaps deriving from surface freshwater ancestors which have become extinct. Ongoing molecular research will clarify their evolution. Each species and subspecies is endemic to a restricted karstic system. Monolistra schottlaenderi is exclusive to saturated aquifers of the Karst in the areas of Trieste and Isonzo, and is the only Italian member of the subgenus Microlistra, which also lives in Slovenia and Croatia. The species of this subgenus have knobby dorsal protrusions, and sometimes even long, robust spines that function as efficient defensive structures when the animal curls into a ball. Among other species, with smooth teguments, there is Monolistra julia, endemic to caves in the Julian Pre-Alps, where it lives in small streams of trickling water. It has two well-developed caudal appendages (uropods). Other species do not have uropods, which may be atrophic or barely visible. The furthest west (Monolistra pavani) is found in the underground stream of the Buco del Piombo (Como). Monolistra racovitzai (ca. 5x) 63
64 Species of genus Niphargus; top: N. costozzae; centre: N. longicaudatus; left, bottom: N. pescei (top) and N. transitivus (bottom); right, bottom: N. bajuvaricus grandii (ca. 3x) ■ Amphipods This order of malacostracans includes several marine and freshwater species, sometimes sub-terrestrial, which colonised groundwater either directly from the sea, or from ancestors that once inhabited limnic surface water. In Italy, there are about 100 stygobiont species, almost all of which are endemic. Bogidiellids. Italian freshwaters host seven stygobiont species, most of Bogidiella sp. (ca. 10x) which are interstitial, occasionally euryhaline. Bogidiella albertimagni (in the Po Plain) and Bogidiella aprutina are the only continental species; the others are Tyrrhenian endemics, found in Sardinia and on the island of Elba. Gammarids. This family comprises exclusively surface species. Among those which only live in groundwater and are Italian endemics, two species of Tyrrhenogammarus live in karstic aquifers in south-eastern Sicily (Tyrrhenogammarus catacumbae) and Sardinia (T. sardous). One species of Longigammarus (L. planasiae) has recently been collected from a well on the limestone island of Pianosa (Tuscan archipelago), and a specialised species, Ilvanella inexpectata, is known to inhabit alluvial aquifers on the island of Elba and in Tuscany. Hadziids. The genus Hadzia - presumably a Tethyan relict - has four Italian species. Hadzia fragilis stochi, an endemic subspecies with delicate, elongated appendages, has been described in alkaline water in the karstic area of Trieste and river Isonzo. Hadzia minuta inhabits karstic waters in Salento, and H. adriatica has been collected from pools in Apulia. Another species, which is still under description, was recently found in southern Sardinia. Niphargids. The genus Niphargus (more than 250 known species, 70 of which live in Italy; size between 3 and 40 mm) have complex, controversial taxonomy, which is currently being revised by means of molecular biology techniques. Their distribution area includes most of Europe (except for the Iberian Peninsula and the upper northern areas) and stretches east towards Iran. This suggests that the genus colonised European surface freshwater from the basins of the Tertiary Paratethys, and later moved into groundwater. However, fossils similar to present species have recently been found in Baltic 65
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: 60 those associated with percolatin
Page 15 and 16: 68 ■ Decapods Italian fauna has o
Page 17 and 18: 72 Stygofaunal provinces in Italy T
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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