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The endemic fauna of the sicilian islands 255

part of the populations have allegedly faced local are, as a matter of fact, a fragment of Sicily, to
extinctions as a result of the processes of competitive which they alternately remained connected during
exclusion derived by the colonisation of the ar- the eustatic variation in Pleistocene, and from
chipelago by the lizard P. siculus (Rafinesque- which they are separated by a sea bed only 40 m.
Schmaltz, 1814) (Lo Cascio, 2010). deep (Ruggieri, 1973; Agnesi et al., 1993), the last
However, to the antique datation of the molecu- time durind Würmian glaciation (until about 12,000
lar clock for P. raffoneae we need to add the diffi- years ago) (Massa, 1973; Ruggieri, 1973). On the
culty to explain the presence of terrestrial molluscs contrary, Marettimo originated almost exclusively
with high preference for calcium. Among these from Triassic sediments that show no similarities to
ones Hypnophila incerta (Bourguignat, 1858), the Sicilian territory as they are correlated to surfa-
present in many of these islands, Oxychilus (Hyalo- cing present in northern Africa and Iberian Penin-
cornea) alicurensis of Alicudi and O. (Oxychilus) sula (Ruggieri, 1973). Furthermore, it is separated
lagrecai of Filicudi. As such, the genesis of Hy- from the two other islands by a channel (“Maret-
gromiidae Helicotricha carusoi Giusti, Manganelli timo Channel”) whose maximum depth is 350 m,
et Crisci, 1992, is hard to interpret as it belongs to enough to prevent connections with the Sicilian
a genus that is endemic of the Aeolian and implies territory during Pleistocenic regressions (Agnesi et
a very long time for its differentiation. al., 1993). These pronounced differences also
Giusti (1973) hypothesizes the existence of reflect, as it is right to expect, on faunistic popula-
ancient groups of territories above sea level which tions of the three islands. Marettimo, as pointed out
left groups of paleo-endemic species to the new by several authors (Alicata, 1973; Bordoni, 1973;
Aelioan islands of formation. These territories Caruso, 1973; Lanza, 1973; Magnano & Osella,
might have been situated further north, and even 1973), is characterized by a pre-quaternary popula-
derived by the fault of Tyrrhenian microplates in tion with predominant similarities with the western
their shift towards their present position, or further Mediterranean. Favignana and Levanzo show
south, in contact with the Sicilian coast line. poorer endemic populations and generally with
A different biogeographical explanation was Sicilian affinities (Canzoneri, 1968). As a whole, 20
proposed for Ocys beatricis Magrini, Cecchi et Lo endemic entities are known in the archipelago, 18
Cascio, 2000: a small carabid, endemic in Lipari of which are present in Marettimo alone. Levanzo
and rather isolated in the field of its genus and only has scarcer endemic contingents (6 taxa, only one
akin to another specie, Ocys inguscioi Magrini et of which - gastropod Rupestrella rupestris coloba
Vanni, 1992, localised in southern Puglia. Con- (Pilsbry, 1918) - exclusive of the island) and Fav-
sidered that these are winged species, potentially ignana (6 taxa, all in common with the other islands
capable of highly dispersive capacities, it is possible of the archipelago). Two endemic vertebrates are
to suppose a climate or ecological change to have present - the Soricid Crocidura sicula aegatensis
caused the disappearance in the original distribution Hutterer, 1991, present in all of the three islands,
area of a common hypothetical ancestor, and the and the lacertid Podarcis waglerianus marettimen-
distance between the surviving population to have sis (Klemmer, 1956) in Marettimo alone - whose taxo-
triggered a differentiation on a species level (Mag- nomic status, besides, is considered rather doubtful
rini et al., 2000; Lo Cascio & Navarra, 2003). The (Capula, 1994; Sarà, 1995). Invertebrates make up
endemic sub species of garden dormouse present in the largest endemic element under the biogeo-
Lipari, Eliomys quercinus liparensis Kahamann, graphical profile. In the field of the endemic fauna
1960, differentiated, according to several authors of Marettimo we need to highlight the presence of
(see Angelici et al., 2009) starting from nuclei ori- interesting paleoendemic species, such as the un-
ginally introduced in the Roman age for dietary. derground Coleoptera Typhloreicheia (Typhlor-
eicheia) berninii Magrini, Bastianini et Petrioli, 2003
Egadi Archipelago and Alaocyba ientilei Baviera, 2010; the Gastropods
Oxychilus (Hyalofusca) denatale (Pfeiffer, 1856),
The three major islands of the Egadi are of sed- Siciliaria scarificata (Pfeiffer, 1856), Marmorana in-
imentary origin, different from the geological and sularis (Benoit, 1857) and Schileykiella bodoni Cian-
paleogeographic history. Favignana and Levanzo fanelli, Manganelli et Giusti, 2004; the Tenebrionid