Page 1 - Muscarella_Baragona_2017

Biodiversity Journal, 2017, 8 (1): 249–278 MONOGRAPH

The endemic fauna of the sicilian islands

1
Calogero Muscarella & Alessandro Baragona 2

1 Via D’Ondes Reggio 8/A Scala G, 90127 Palermo, Italy; e-mail: calogero@silenecoop.org
2 Via Piersanti Mattarella 5, 90020, Sciara, Palermo, Italy; e-mail: alessandro.baragona@gmail.com

ABSTRACT In this survey we propose an analysis of the endemic fauna (Mollusca, Arthropoda, Chordata)
present in the 14 major circum-sicilian islands and in Lampione islet (Strait of Sicily, Pelagie
Islands). Overall, 111 endemic taxa between species and subspecies have been identified. The
largest taxonomical groups are Tenebrionid Beetles and Curculionids (respectively 18 and 16
taxa) and Gastropods (20 taxa), due to their strong inclination to insular differentiation, which
is inversely proportional to their vagility. The number of endemic taxa per island is positively
associated to the extent of the surface but not to the distance from the closest continental mass
or altitude or geological origin. The most important connection is with the complex paleo-
geographic history pertaining the different insular complexes.

KEY WORDS Endemism; circum-sicilian islands; paleogeography.

Received 15.03.2016; accepted 11.11.2016; printed 30.03.2017
Proceedings of the 3rd International Congress “Biodiversity, Mediterranean, Society”, September 4th-6th 2015, Noto-
Vendicari (Italy)

INTRODUCTION or “chersogenic” islands; in the second one, about
“talassogenic islands” (see also Troia, 2012 and cor-
Small islands and archipelagoes have always responding bibliography).
raised the interest of biologists, especially due to The organisms actively or passively colonizing
the peculiar flora and fauna which inhabits them the islands undergo a severe selective pressure
(Pasta, 2008; Minelli, 2012). The Mediterranean is triggered by both isolation and environmental
a sea basin gathering one of the largest insular characteristics; as an adaptative response, they
groups in the world with approximately 5000 is- develop more or less pronounced biological pecu-
lands. This number raises up to approximately liarities, favouring the formation of endemic species
11,879 if we consider the numerous minor islands (cf. Zunino & Zullini, 1995) (Figs. 1–4).
as well (Blondel et al., 2010). The coastline of these Several factors contribuite to the birth of these
islands extends for approximately 18,000 km, in- endemic species: paleogeography (a few have re-
cluding 39% of all the Mediterranean coastal areas mained isolated for a long time, others have not),
(cf. ANPA, 2001). The islands of the Mediterranean distance from the nearest continental mass (source
are, for the most part, strips of land above sea level area), size of the island (between a few square
which have latterly isolated themselves from the metres and 25,700 square km as is the case of Sicily,
nearby continental masses. Other islands are of vol- for instance), height above sea level, substrate, mor-
canic origin and have never had contacts with other phology. These factors, as a whole, have determined
lands. In the first case we speak about continental the high rates of endemism that have been observed