Preprint volume - SIBM

Pre-print Volume - Posters
BENTHOS COMMITEE
M.C. MANGANO, E. PORPORATO, F. DE DOMENICO, A. PROFETA*, B. BUSALACCHI*, N.
SPANÒ
Dip.to di Biologia Animale ed Ecologia Marina, Università di Messina, Salita Sperone, 31 - 98166 Messina, Italia.
mmangano@unime.com
*Istituto Sperimentale Talassografico – CNR, Spianata San Ranieri, 86 - 98122 Messina, Italia.
LEPTOMETRA PHALANGIUM (J. MÜLLER, 1841)
FIELDS FROM THE SOUTHERN TYRRHENIAN SEA:
PRELIMINARY DATA ON THE ASSOCIATED FAUNA
FAUNA ASSOCIATA AI CAMPI A LEPTOMETRA PHALANGIUM
(J. MÜLLER, 1841) NEL MAR TIRRENO MERIDIONALE: DATI PRELIMINARI
Abstract – The crinoid Leptometra phalangium (Echinodermata: Crinoidea) is considered as an indicator
of highly productive areas along the continental shelf capable to sustain large biomasses of benthopelagic
fish. The presence of L. phalangium fields was recently recorded in the Southern Tyrrhenian Sea and the
demersal associated fauna was identified. These results, according to other Authors, provide further
evidence on the importance of this facies in structuring demersal communities and in enhancing the habitat
heterogeneity, confirming the importance of L. phalangium field as essential fish habitat.
Key-words: Leptometra phalangium, demersal fauna, southern Tyrrhenian Sea.
Introduction – The suspension feeder crinoid Leptometra phalangium (J. Müller,
1841) represents a typical component of the Mediterranean benthic community of the
continental shelf (DL, Pérès and Picard 1964), where can locally reach very high
density (Kallianotis et al., 2000; Colloca et al., 2003). The aggregation zones of this
species are considered able to sustain large biomasses of benthopelagic fish also
playing an important role for their recruits (Colloca et al., 2004). In this note some
information on demersal species associated with L. phalangium facies in the Southern
Tyrrhenian Sea are reported.
Materials and methods – Data were collected during a trawl survey carried out with
CNR vessel “Dallaporta” in the Southern Tyrrhenian Sea in spring 2009. The hauls
were performed using a trawl net having a 20 mm mesh size cod-end between 20 and
133 meters of depth from Brolo (ME) to Capo Raisigerbi (PA). All species collected
were identified, counted and weighed. Data were elaborated in accordance with swept
area of each haul to obtain the Density (n/km 2 ) and Biomass (kg/km 2 ) indices.
Results – The presence of L. phalangium in facies was recorded in two localities: off
Santo Stefano di Camastra (ME) from 128 to 133 meters, presenting a density of 1650
ind./Km 2 and off Finale di Pollina (PA) from 113 to 117 meters, with density of 2220
ind./km 2 . A total of 33 demersal species was collected: 23 Osteichthyes, 1
Chondrychthyes, 8 Mollusca and 1 Crustacea. The most abundant species (>3%) are
reported in table 1.
In this bottom we found typical demersal species already known for the L. phalangium
fields from other areas of the Tyrrhenian Sea (Colloca et al., 2004; Reale et al., 2005).
Conclusions – Although the L. phalangium bottoms are not rare in the Tyrrhenian Sea,
this is the first official record of this facies along the Sicilian Tyrrhenian coasts. Our
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