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Fattorini & Dapporto
Revista de Gestão Costeira Integrada / Journal of Integrated Coastal Zone Management 14(2):185-197 (2014)
(out of 26 taxa; 3.8%) and two endemic taxa (Heliopathes
avarus donatellae and Probaticus cossyrensis) from Pantelleria
(out of 23; 8.7%). Only a fraction of the surface of these two
islands is protected. The “Riserva naturale orientata Isola di
Ustica” covers 204.36 hectares, i.e. 23.76% of Ustica’s area,
whereas the “Riserva naturale orientata Isola di Pantelleria”
occupies an area of 2626.69 hectares, i.e. about 30% of the
island’s area. However, in both islands there is some habitat
variability represented by presence of coastal areas, pine
woods and maquis. Pantelleria in particular hosts a great
mosaic of environmental variability including the Venere
lake area, different woods around the Montagna Grande area
and traditionally managed agricultural areas.
The Pelagie Islands are remote and very ancient islands.
The island of Lampedusa (the largest amongst the Pelagie)
shows a relatively rich tenebrionid fauna, including 28 taxa,
4 of which (Erodius audouini destefanii, Pachychila dejeani
doderoi, Alphasida puncticollis tirellii, Asida minima; 14.3%)
are endemic to this island. This island was included in the
third quartile by both BCC1 and BCC2. Lampione, an islet
of just 0.03 km2, hosts six tenebrionid taxa, three of which
(Alphasida puncticollis moltonii, Tentyria n. sp. and Opatrum
validum rottembergi) are endemic to this island, and one
(Machlopsis doderoi), endemic to the Pelagie Islands, occurs on the islands in the Tuscan Archipelago, such as the very small
Lampedusa and Lampione. Nineteen species are known from
Linosa, with no exclusive endemic (although it is not clear if
the Tentyria population of this island belongs to an African
species or it is an endemic species), but Stenosis brignonei is paleogeographical history of this archipelago, with the
endemic to Linosa and Lampedusa, and Linosa was included
in the first quartile by the BCC1 index and the BCC1p index
as well as by all BCW indices. The “Riserva naturale orientata
Isola di Lampedusa” covers 369.68 hectares, i.e. about 15%
of the island’s area. The “Riserva naturale orientata/integrale populations endemic to individual islands or to groups of
Isola di Linosa e Lampione” (266.87 hectares) covers about
49.5% of Linosa (as an oriented nature reserve) and 100%
of Lampione (as a strict nature reserve).
As a whole, Pantelleria and the Pelagie Islands host
several species, more or less widely distributed in North
Africa (especially Algeria and Tunisia), which occur in
Europe only on these islands, like Imatismus villosus and
Pseudoseriscius griseovestis on Linosa; Pachychila crassicollis
cossyrensis and Opatrum validum schlicki on Pantelleria;
Pachychila tazmaltensis, Eutagenia aegyptiaca tunisea and
Microtelus lethierryi on Lampedusa; Allophylax costatipennis
costatipennis on Lampedusa and Linosa; Gonocephalum
perplexum on Lampedusa and Pantelleria. Thus, although
Pantelleria and the Pelagie islands host few species, as
expected because of their very small area and high isolation,
their tenebrionid faunas are very peculiar, which leads to a
high prioritisation.
All other islands selected by one or more indices belong
to the Tuscan Archipelago. The Tuscan Archipelago is
composed of seven main islands (Elba, Giglio, Capraia,
Pianosa, Montecristo, Gorgona and Giannutri) and several
islets located in the Tyrrhenian Sea, between Corsica and the
Italian Peninsula. Main islands range from 2.2 km2 (Gorgona)
to 223.5 km2 (Elba). The islands differ considerably in
terms of their origin and geological features. The island of
Gorgona is composed by both sedimentary and ophiolitic
rocks. The island of Capraia is volcanic and originated about
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nine million years ago. The island of Montecristo is entirely
granite, as is most of the Island of Giglio. The island of Elba
shows a more composite origin, being granite in the western
part (where Mount Capanne reaches 1018 m elevation),
sedimentary and metamorphic in the central and eastern
part (with gneiss and marble rocks) and alluvial (with clay,
sandstone, and limestone soils) in the central plains. The
island of Pianosa is composed of sedimentary rocks and shell
formations. A total of 59 native taxa are known from these
islands, 13 of which (22%) are endemic. Out of these 13
endemics, one (Asida gestroi) is classified as species, the others
being represented by populations classified as subspecies. The
percentage of endemic taxa (single island endemics and taxa
endemic to the archipelago) varies considerably among the
main islands, ranging from 5.88% (Elba, with two endemic
taxa out of 34 taxa) to 55.56% (Montecristo, with 5 endemic
taxa out of 9 taxa), whereas the islets have higher levels of
endemism (67-100%) but with very few species (1-3 taxa).
This is due to the fact that islets are colonised from adjacent
islands by taxa that are endemic to the archipelago, but
which are widespread within it. It has been suggested that
for animals with low mobility (Fattorini, 2010a), islets tend
to be colonized by adjacent islands more than by mainland
areas, and this is probably the case of the islets surrounding
rocks around Elba island.
Levels of endemism can be explained by the
islands which were isolated for longer showing higher levels
of endemism (Fattorini, 2009a, b). Most endemics are
associated with garrigue and maquis biotopes. Some taxa
show an impressive cladogenesis, being represented with
a few islands, such as Asida luigionii (with two subspecies,
doriai and insularis), the endemic A. gestroi (with the
subspecies gestroi, tyrrhena, capraiensis, lanzai, and gardinii),
and Opatrum sculpturatum (with the endemic subspecies
ilvense, urgonense, capraiense and igiliense). The only endemic
taxa likely associated with woodlands are Colpotus strigosus
oglasensis and Odocnemis ruffoi osellai.
All islands of the Tuscan Archipelago are part of a National
Park and most of their environmentally valuable areas are
under strict protection. In particular all the entire island
of Montecristo represents a biogenetic reserve established
in 1971. Only two peoples live there, both nature reserve
keepers. Visitors are highly restricted in yearly number and
activities. Also on Gorgona and Pianosa access is regulated,
but other islands were subject to high tourism pressures,
notably Elba and Giglio. Despite the human population
on the Tuscan Islands is relatively small and declining (e.g.,
de Fabrizio, 2005), there have been important anthropic
influences. Serious consequences have been produced by
past growth of mass tourism (and partly also of the so-called
ecotourism). This has resulted in the rapid degradation
of the most fragile natural habitats especially before the
establishment of the National Park. The effects have been
especially serious on the coastal environments, which
became more and more attractive to tourists just because
of their increasing rarity. This is the case of the few and
scattered sandy shores on Giglio, now completely obliterated