Preprint volume - SIBM

Pre-print Volume - Oral presentations
Topic 2: MARINE ORGANISMS AND ECOSYSTEMS AS MODEL SYSTEMS
P.G. ALBANO, B. SABELLI, M. ADANI 1 , N. PINARDI 2
Dipartimento di Biologia Evoluzionistica Sperimentale, University of Bologna, Via Selmi, 3 - 40126 Bologna,
Italia.
pgalbano@iperbole.bologna.it
1 Istituto Nazionale di Geofisica e Vulcanologia, Gruppo Nazionale di Oceanografia Operativa, Bologna, Italia.
2 Centro Interdipartimentale di Scienze Ambientali, University of Bologna, Via S. Alberto, 163 - Ravenna, Italia.
THE TERMOPHILOUS SPECIES ECHINOLITTORINA PUNCTATA
AS A NEW DESCRIPTOR OF TROPICALIZATION
IN THE MEDITERRANEAN SEA – FIRST DATA
LA SPECIE TERMOFILA ECHINOLITTORINA PUNCTATA: NUOVO
INDICATORE DI TROPICALIZZAZIONE DEL MEDITERRANEO – PRIMI DATI
Abstract – Data suggest that the prosobranch gastropod Echinolittorina punctata (Gmelin, 1791)
(Mollusca, Gastropoda) has extended its range northwards along the Italian coastline due to climate
variability in marine conditions. Its ease of identification and mesolittoral habitat suggest this species may
be a new practical indicator of Mediterranean Sea changing conditions, easy to monitor.
Key-words: Mollusca, climatic changes, indicator species, intertidal environment, Italy.
Introduction – The scientific investigations of the past decade demonstrated that the
climate observational record contains warming trends. Small and semi-enclosed seas
like the Mediterranean can react faster to the causes of these temperature trends and in
turn the changes in temperature can force changes in the biota due to both by Non
Indigenous Species (NIS), most of them of warm-water affinity, and by significant
distribution shifts of autochthonous warm-water affinity Indigenous Species (IS).
The effects of Non Indigenous Species lead to the “tropicalization” of the
Mediterranean Sea, while the north-wards range expansion of autochthonous species
leads to its “meridionalization”. However, Bianchi (2007) suggests that both
phenomena respond in a similar way to the same drivers and could be treated as a
single phenomenon.
Echinolittorina punctata (Gmelin, 1791) is an autochthonous Mediterranean
prosobranch gastropod living on mesolittoral hard substrates. It used to be distributed
mainly along the Southern and Eastern Mediterranean shores. Known for Sicilia since
the mid-20 th century only (Antit et al., 2007), its range has extended northwards along
the Tyrrhenian coastline and is now reported as north as Civitavecchia (P.G. Albano,
unpublished data). New stations were reported from Puglia too (Albano & Trono,
2008).
The northward extension of the species along the Tyrrhenian coastline could be simply
favored by the characteristic northward currents transporting planktonic larvae.
However it is difficult to consider this as the main cause of northward displacement
since the species were largely present only in the southern coasts until a decade ago.
Therefore, a climate trigger could be taken into consideration to explain the northward
shift. This hypothesis was reinforced by the seasonality of the reproductive cycle which
takes place during the summer months (Palant & Fishelson, 1968) thus affecting the
species recruitment.
41 st S.I.B.M. CONGRESS Rapallo (GE), 7-11 June 2010
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