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746 Alfred Uchman, Andrzej Ślączka and Pietro Renda
external moulds of fossils. If they are
body fossils of roots, the Interna-
tional Code of Botanical Nomencla-
ture allows consideration of anatomi-
cal parts of a fossil plant as taxa (see
McNeill et al., 2006; Division II,
Chapter 1, Article 1.2). So, if they are
roots their taxonomic description is
still possible. In all cases, their taxo-
nomic treatment imposes a descrip-
tive discipline and makes compari-
sons easier, even if their systematic
position is unclear.
GEOLOGICAL SETTING
Favignana Island belongs to the
Aegadian Islands (Fig. 1) that repre-
sents an emerged part of the Egadi
Thrust Belt (Abate et al., 1995, 1997)
of the Sicilian–Maghrebian system.
Favignana is mainly a build-up of
Mesozoic–Upper Neogene carbon-
ate deposits, which are unconform-
ably covered by Middle–Upper Plio-
cene bluish marls and shales fol-
lowed by Lower Pleistocene light
Fig. 1. Index map with locations of the sites studied calcarenites and calcirudites (Fig. 2).
These deposits are covered by
Geological map of Favignana Island redrawn from Abate et al. (1997) Tyrrhenian calcarenites and bio-
rudites with Strombus bubonius,
which are separated from the underlying deposits by a reddish
erosional discontinuity. The Lower Pleistocene deposits are
widespread along the eastern slope of the emerged palaeo-
Favignana Island in a pull-apart basin, and are a part of a wide
shoal that is attached to western Sicily and embraces the
Aegadian Islands. The calcarenites have been quarried since
Roman times. The Lower Pleistocene deposits represent a high
energy coast with beach to offshore successions and a mobile
bar system (Ślączka et al., 2011). Several facies associations
are distinguished on the basis of bedform characteristics, sedi-
mentary structures and ichnological features. They show an or-
der in their distribution eastwards from the shoreline of the
palaeo-Favignana Island, as described below. The fore-
shore-shoreface facies association generally is represented by a
coarsening up sequence of calcarenites and conglomerates,
which contain rare short, vertical tubular burrows. The upper
shoreface facies association is characterized by calcirudites
with several algal remains and rhodoliths, and these beds are
separated by erosional surfaces that display Thalassinoides and
Ophiomorpha. The upper-middle shoreface facies association
is interpreted as the deposits of a bar system with erosional
channels. Locally, it contains strongly bioturbated horizons and
trace fossils of the Skolithos ichnofacies. The lower shoreface
Fig. 2. Stratigraphic column of Favignana Island facies association is represented by a thick sequence of
(after Abate et al., 1995, modified) large-scale cross-bedded and subhorizontal laminated
bedforms (outer bar system). Totally bioturbated horizons,
mostly with echinoid burrows, mainly Scolicia, related to
