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2. MATERIAL AND METHODS
Sediment samples were collected by a Van Veen grab (12 l), during two

oceanographic cruises of the research vessel “Bannock”. The first cruise took place
between July and August 1983 along the coasts of Ustica Island, Egadi and Aeolian
Archipelagos. A total of 270 grab samples were collected in 134 stations between 15
and 540 m (station lists and bottom features in Albertelli et al., 1987). The second
cruise took place in October 1984 in the Partenopean and Pontine Archipelagos for a
total of 263 grab samples collected in 123 stations between 22 and 152 m depth (Fig. 1).
On board, sediment samples were sieved throughout a 2 mm mesh net and fixed in
buffered formaldehyde (10 % in seawater). In laboratory, crustaceans were sorted,
identified until species level and preserved in ethanol (75 %).

Cluster and SIMPER analyses (on a matrix of presence/absence transformed data)
and the Shannon diversity (log2) and evenness calculations were performed using the
software PRIMER.
Text abbreviations used in tables and figures are: Egadi Archipelago: MA =
Marettimo, LE = Levanzo, FA = Favignana; Ustica Island = US; Aeolian
Archipelago: FI = Filicudi, SA = Salina, LI = Lipari, ST = Stromboli,VU = Vulcano,
PN = Panarea; Pontine Arcipelago: VE = Ventotene, SS = Santo Stefano, PO = Ponza,
PA = Palmarola, ZA = Zannone; Partenopean Arcipelago: PR = Procida, CA = Capri,
IS = Ischia.

Fig. 1 - Study site.

3.RESULTS AND DISCUSSION
On the whole, we found 1001 specimens belonging to 184 species (Tab. 1 and

complete species list in Tab. 2). The Ustica Island showed the highest number of
individuals (total 246, on average 18.4±5.1), and of species (total 38, on average

169