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New brooding echinoid from the Italian Pleistocene 3
southern Italy and correlate with deep-sea sapropels probably lived and developed during a cooling trend; cer-
(Lickorish & Butler 1996; Pomar & Tropeano 2001; tainly, assemblages from north-western France
Roveri & Taviani 2003; Massari & Chiocci 2006). How- (Neraudeau et al. 2003) developed when this area was no
ever, the Gelasian was, generally, a period of relatively longer subject to tropical-subtropical conditions (Mone-
warm conditions in the Mediterranean (Monegatti & Rafï¬ gatti & Rafï¬ 2007 with references). Above the latitude of
2001), with a climate similar to or possibly slightly 50 N, in the southern North Sea Basin, colder conditions
warmer (at least during interglacials) than that in the likely occurred during the deposition of the Coralline
present-day Mediterranean, and may represent a key time Crag and the Red Crag. However, the climatic setting of
for understanding what may be expected before the onset the Coralline Crag, as well as of the southern part of the
of the warm conditions projected for the end of the 21th North Sea Basin during the earlyÀmiddle Pliocene, is
century. A remarkable unevenness has typiï¬ed the Early controversial since both subtropical and cold-water mol-
Pleistocene Mediterranean climate since the end of the lusc species, such as the boreal bivalve Arctica islandica
Gelasian, at about 1.8 Ma. From this time on, warm condi- (Linnaeus, 1767), are found within this stratigraphical
tions with low seasonality (Garilli 2011) have alternated range (Monegatti & Rafï¬ 2007; Johnson et al. 2009; Wil-
with colder periods with higher seasonality (Rafï¬ 1986). liams et al. 2009 with references; Long & Zalasiewicz
Climatic differences between interglacial (warmer) and 2011). Possibly, the area underwent a more or less marked
glacial (colder) settings have become more marked since alternation of colder and warmer periods, similar to that in
the onset of the harsher Ice Ages at about 0.8 Ma. the Calabrian of the Mediterranean area.
Downloaded by [vittorio garilli] at 22:43 08 June 2016 An overview on the distribution of Geological setting
Temnopleuridae
The investigated deposits are all in northern and southern
The family Temnopleuridae includes 16 genera, whose Italy, in a general geological setting that reflects the geo-
oldest records date back to the Eocene of southern Asia dynamic evolution of the central Mediterranean area,
and Australia. Since then the family has spread into a namely the result of complex interactions between exten-
wide area mainly consisting of Australia, the Indian sional and collisional tectonic processes controlled by the
Ocean and the Indo-West Paciï¬c area, with several gen- compressive motions of the African and Eurasian plates
era, most of which are still living within a latitudinal and their microplates, such as the Adriatic and Apulian
range of about 41 S to 41 N (Fig. 1). Up to now, there microplates (Dewey et al. 1989; Scrocca et al. 2003).
have been no fossil or living records of the family docu- These processes generated the Alpine, the northern Apen-
mented in the Mediterranean area. Although no Temno- nine and the southern Apennine-Maghrebian chains, and
pleuridae are present today in the north-eastern Atlantic, a the Tyrrhenian back-arc basin, which are the main tec-
few genera of this family were well represented in that tonic elements in central Mediterranean (Fig. 2A).
area during the late Neogene and the Early Pleistocene.
The genus Temnechinus Forbes, 1852 was ï¬rst described The study sites in northern Italy (Fig. 2AÀC) are in the
from the ZancleanÀ(?)early Piacenzian (Head 1998; Adriatic-Apulian foreland structural domain, close to the
Monegatti & Rafï¬ 2007 with references) Coralline Crag main thrust of the Northern Apennines (Fig. 2A), a thrust
and the very late PiacenzianÀmiddle Gelasian (Williams belt developed mainly in Neogene times during the east-
et al. 2009) Red Crag formations (Agassiz in Agassiz & ward roll-back of the subducting Adriatic plate (Scrocca
Desor 1846; Forbes 1852) of England. Subsequently it et al. 2003). They belong to the late PlioceneÀEarly Pleis-
was also cited from north-western France (Roman 1983; tocene succession of the western Emilia Romagna, which
Neraudeau et al. 2003) and The Netherlands (Jagt & formed in the north-western part of the palaeo-Adriatic
Idema 2002). Interestingly, a rich and diverse marsupiate Basin under the control of a fan-delta system (Pervesler
temnopleurid fauna has been described from the late Mio- et al. 2011). The late Pliocene deposits have been
cene (Messinian) and Pliocene of north-western France regarded as a regressive succession transitioning from
(Roman 1983; Neraudeau et al. 2003; Dudicourt et al. outer to inner shelf; the overlying Pleistocene deposits
2005), where the genera Temnechinus, Coptechinus Cot- formed in shelf, nearshore, and transitional environment
teau, 1883 and Tremaster Dudicourt et al., 2005, with ï¬ve in a shallowing-upward trend (Dominici 2001, 2004; Per-
species, have been reported. This fauna is strongly differ- vesler et al. 2011). Three of the deposits studied in north
entiated from the coeval Mediterranean echinoid assemb- Italy formed in the Castell’Arquato Basin, a satellite basin
lages, which had a markedly thermophilic character of the Adriatic foredeep, where late Neogene sediments
(Neraudeau et al. 2003). The late Cenozoic temnopleurid- overlie the Mesozoic Ligurian complex (Roveri & Taviani
rich assemblage from north-western Europe therefore 2003). Several calcarenite bodies crop out in this basin,
particularly the system tracts of the sequences bounded by
the 3.1, 2.7 and 2.1 Ma (late PiacenzianÀlate Gelasian)
