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6 E. Borghi and V. Garilli

Downloaded by [vittorio garilli] at 22:43 08 June 2016 et al. 2012). A remarkable subsidence phase occurred at Figure 3. Scatter diagrams of some morphological parameters
about 2.3À2.1 Ma, triggering a generalized, marked deep- of Placentinechinus davolii gen. et sp. nov.; diameters of A, the
ening of the basin in the middleÀlate Gelasian (Capraro apical system (Da) and B, the peristome (Dp) plotted against the
et al. 2006). This phase correlates with the precession- test diameter (D), n D 132.
controlled sapropels B1-B7 of Lourens et al. 1996 (Cap-
raro et al. 2006). The deepening trend seems to have Punta Marsala respectively, in the south-eastern part of
occurred up to the late Calabrian, throughout the large Favignana Island (Aegadian Archipelago, off western
Gephyrocapsa zone (Scarponi et al. 2014). Sicily). Four specimens from sites P1À2 and C1 were col-
lected by Luca Bertolaso (Correggio, Italy).
The southernmost investigated sites are from the Favig-
nana Island, Aegadian Archipelago, a few kilometres off The material is housed at the Museo Geologico G. Cor-
the western coast of Sicily (Fig. 2A, F). The archipelago tesi of Castell’Arquato, near Piacenza (northern Italy),
is an emergent part of the Egadi thrust belt (Abate et al. with the inventory code MG. Most specimens are pre-
1995, 1997), within the Sicilian Maghrebian system (Sulli served as complete coronas and were picked up by hand.
2000; Nigro & Renda 2001). This area represents the Some of these tests still preserve spines. Sieved bulk
westernmost sector of the Sicilian orogenic belt, which is samples provided test fragments, loose spines and lantern
mainly comprised of Neogene south-verging fold-thrust ossicles, but no apical plates were found. Detailed morpho-
tectonic elements (Tondi et al. 2012 and references logical analyses were carried out using a Zeiss DSM 940
therein). Favignana Island is formed by Triassic to Eocene and a Jeol JSM 5610 LV scanning electron microscope at
deposits, cropping out in its western part, unconformably the Salamanca University (Spain) and at the Museo Civico
covered by late Cenozoic sediments that mainly consist of di Storia Naturale of Milano (Italy), respectively.
Early Pleistocene calcarenites and calcirudites. Our sites
belong to these Pleistocene calcarenite deposits, which A bivariate statistical biometric analysis (Fig. 3) on the
have been compared to the Apulian Calcarenite di Grav- new species described was carried out based on 133 whole
ina Formation (Sla˛czka et al. 2011 and references tests, 122 of them collected from the layer immediately below
therein); they crop out mainly in the eastern slope of the the calcarenite bed at site E1 (see hereafter and Fig. 4), 10
emerged palaeo-Favignana, in a pull-apart basin. Gener- from sites F1À2, one from site P1. The species has been
ally, these deposits have been interpreted as having been defined by four raw test measurements, D, H, Dp and Da, and
formed in a moderate to high energy coast with beach to three shape ratios, Da/D, Dp/D and H/D (Table 1).
offshore successions and a mobile bar system (Sla˛czka
et al. 2011; Slootman et al. 2012). Several litho- and icn- Classification follows Kroh & Smith (2010).
hofacies have been recognized within the calcarenites in
Favignana (Tondi et al. 2012; Uchman et al. 2012). Study sites

Material and methods Sites from north Italy. Most specimens were collected
from the E1 site (4451019.1600 N 952027.1000 E), in the
Measurement abbreviations
D, test diameter measured at the ambitus; Da, diameter of
the apical system; Dp, diameter of the peristome; H, test
height; nA and nIa, maximum number of plates in ambu-
lacral and interambulacral columns, respectively.

Material and biometric analysis
The studied material consists of 189 specimens, collected
(mostly by the first author) from the following late Ceno-
zoic Italian sites (Fig. 2): E1 (Castell’Arquato, Arda
River, Piacenza), E2 (San Nicomede, Stirone River,
Parma), E3 (Rio Gisolo, Fidenza, Parma) and E4 (San
Polo d’Enza, Reggio Emilia), all in Emilia Romagna,
north Italy; P1 (Cala Corvino, Monopoli, Bari) and P2
(Torre Sant’Andrea, Otranto, Lecce), both in Puglia, south
Italy; C1 (at about 0.5 km NNE from Sant’Anna village
and a few metres from European route E90) near Crotone,
Calabria, south Italy; F1 and F2, at Grotta Perciata and