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Allophylax costatipennis costatipennis (Lucas, 1846), graphical or environmental gradient may have very dif-
Pachychila tazmaltensis Desbrochers des Loges, 1881, ferent effects on different aspects of species distributions
Eutagenia aegyptiaca tunisea Normand, 1936, Gono- and multiple approaches are needed for understanding
cephalum perplexum (Lucas, 1846) and Microtelus lethi- multiple biogeographical patterns.
erryi Reiche, 1860.
ACKNOWLEDGEMENTS. I wish to express my gratitude to P.
Endemicity levels vary considerably among islands, as Lo Cascio for providing information used to define land cover
a result of their different paleogeographical history. For categories for small Aeolian islets not covered by the GIS of the
the Aeolian archipelago, which is very close to Sicily, Italian Ministry of the Environment and Protection of the Terri-
with a paleogeographical distance strongly reduced tory and Sea. Thanks are due P. Leo and A. Aliquò for sugges-
during Pleistocene regressions, only one endemic species tions, and to D. Boukal and two anonymous reviewers for their
(Nalassus pastai Aliquò, Leo & LoCascio, 2006 from comments on a previous version of his paper.
Vulcano) is known. Two endemic taxa are known from
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