together
with the teleost fishes Chalinura mediter-
ranea and
Lepidion lepidion (Jones
in Priede and
Bagley, 2000). Our survey, transacted without
resorting to bait, documented the site-typical faunal
complement. There is no doubt that the abundance
of the Levantine deep water megafauna is remark-
ably low: in 80 hours of video documentation only
three fishes, B. mediterraneus, Cataetyx laticeps and
Chauliodes sloani, were recorded. Although our
methods were not sufficient for quantitative com-
parison with studies made in the western
Mediterranean, the small number of species and
specimens confirms the ichthyofaunal scarcity of
the Levantine Sea, not only compared with the adja-
cent Atlantic Ocean (Haedrich and Merrett, 1988),
but also with the western Mediterranean.
Decapod crustaceans
Twenty-one bathyal decapods were reported
from a faunistic survey of the Catalan sea conduct-
ed between 1983 and 1985 consisting of 39 trawl
samples taken between 1020 and 2011 m (Abelló
and Valladares, 1988), and 28 species were identi-
fied from 57 samples trawled between 862 and 2265
m in 1988 and 1989 (Cartes, 1993). In all, 29 benth-
ic, mesopelagic and bathypelagic decapod crus-
taceans have been identified from the Catalan deep
sea. Fifteen of the 20 decapod species collected dur-
ing the IOLR monitoring surveys are common to
both localities. Of the most common species at
1350-1549 m in the Catalan sea (Cartes, 1993)—
Aristeus antennatus,
Acanthephyra eximia,
Pontophilus norvegicus,
Polycheles sculptus and
Munida tenuimana—only
the first two species occur
in our samples. The most common species in the
Levantine samples, Polycheles typhlops, was more
common on the middle slope than on the lower slope
in the Catalan sea. The cold stenothermal Sergestes
arcticus and Pontophilus norvegicus are absent,
though the pelagic larvae of the former have been
found at a depth of 10 m, and the latter was record-
ed at 50 m (d’Udekem d’Acoz, 1999). Polycheles
sculptus, Munida tenuimana and
Munidopsis serri-
cornis [=
M. tridentata] are known only from the
western basin of the Mediterranean. Plesionika nar-
val, Munidopsis marionis and
Bathynectes maravi-
gna were identified from the Levantine samples and
from the western Mediterranean, but not from the
surveys in the Catalan sea. In a survey of the deca-
pod fauna of the Eastern Ionian Sea at depths
between 1000 and 1500 m, A. antennatus was as
abundant as P. typhlops (Company et al., 2004),
whereas in the Levantine Sea P. typhlops is more
than three times as abundant as A. antennatus.
Amphipod crustaceans
Fifty-two bathyal amphipod crustaceans were
reported from a survey of the Catalan Sea supraben-
tic bathyal communities (552 - 1808 m) conducted
in 1989 and consisting of 10 hauls (Cartes and
Sorbe, 1993), and 82 species were identified from
20 samples trawled between 389 and 1859 m in
1991-92 (Cartes and Sorbe, 1999), compared with
the 22 species identified from 27 hauls in the Levant
Sea. All but one of the amphipod species collected
during the IOLR monitoring surveys,
Stegophaloides christianiensis, have been recorded
from the Catalan Sea. The dominant species on the
upper part of the lower slope (1250-1355 m) in the
Catalan Sea was Rhachotropis caeca, whereas on
the lower part (1860 m) Ileraustroe ilergetes and
Rhachotropis caeca predominate (Cartes and Sorbe,
1999). Ileraustroe ilergetes is the most common and
prevalent species in the Levant Sea, present in 86%
of the samples, as compared with 6.3 and 20.8%
respectively in the upper and lower parts of the
lower slope of the Catalan Sea. However, whereas
R. caeca appears in 36.3% of the samples taken
between 1250 and 1355 m on the Catalan slope, and
its congener, R. rostrata, in only 4.3% of these sam-
ples, along the Levantine coast their abundance is
reversed: R. caeca is present in 33% of the samples
whereas R. rostrata is present in over half. The next
most common species on the lower slope in the
Catalan Sea, Bathymedon sp. A and Andaniexix
mimonectes, are entirely absent from our samples.
Only four species collected in our study are
Mediterranean endemics, whereas of the 154 deep
sea amphipods known from the Mediterranean as a
whole, 71 are endemic species (Bellan-Santini,
1990).
Cumaceans
Twenty-eight bathyal cumacean species were
reported from a survey of the muddy bottoms of the
slope (552-1808 m) of the Catalan sea (Cartes and
Sorbe, 1993), and 32 species were identified from
21 samples trawled between 389 and 1859 m in
1991 and 1992 (Cartes, 1997), compared with the 12
species identified from 27 hauls in the Levant Sea.
All of the cumacean species collected during the
THE BATHYAL FAUNA OF THE LEVANTINE SEA
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IOLR monitoring surveys have been recorded from
the Catalan Sea. The dominant species on the lower
slope in the Catalan Sea was Cyclaspis longicauda-
ta (Cartes and Sorbe, 1993, 1997), whereas only 11
specimens were identified in our samples. The most
common and abundant species in the Levantine
samples, Procampylaspis bonnieri, was more com-
mon on the middle slope (862-989 m) than on the
lower slope in the Catalan sea (Cartes and Sorbe,
1993). The characteristic bathyal cumacean assem-
blage in the western Mediterranean, consisting of C.
longicaudata,
P. bonnieri,
P. armata,
Bathycuma
brevirostre and
Platysympus typicus, is somewhat
modified in the Levant Sea, where C. longicaudata
is replaced by Makrokylindrus longipes, the latter
species again being more common on the middle
slope than on the lower slope in the Catalan sea
(Cartes and Sorbe, 1993, 1997).
Molluscs
Salas (1996:90) found that the molluscan fauna
in the Alboran Sea “becomes scarce below 1000 m
with hardly more than one living specimen per haul,
and the deepest samples at 1433 … and 1742 m …
were barren”. Di Geronimo et al. (2001), who exam-
ined the composition and depth range of molluscs
from the bathyal thanatocoenoses of the southern
Tyrrhenian Sea, have established that the most com-
mon benthic species at 1139-1536 m were, in
descending order, Benthonella tenella, Kelliella
abyssicola, Ennucula corbuloides, and Microgloma
tumidula, of which only the first two species occur
in our samples. The most common benthic molluscs
at depths greater than 1000 m off the Israeli coast
are the Atlanto-Mediterranean and Boreal
Benthonella tenella, Kelliella abyssicola, Yoldia
micrometrica, Cardyomia costellata, Entalina
tetragona, Benthomangelia macra, and
Bathyarca
pectunculoides. The same species were identified by
Janssen (1989) in material sampled by boxcore at a
station off the Israeli coast at 1217 m. Though all are
present in the southern Tyrrhenian Sea, except for
the first three species, they are rather rare (Di
Geronimo et al., 2001).
Levantine low-diversity, low-density
deep water fauna
“The floro-faunistic impoverishment of the east-
ern Mediterranean compared with the western
Mediterranean richness in species” (Sarà, 1985) has
been generally accepted, as well as the perception of
a gradational decrease from west to east that is more
conspicuous for the deep benthos than for the whole
fauna (Fredj and Laubier, 1985): a survey of the
biota of the Balearic basin and the western and east-
ern Ionian Sea at depths between 1000 and 1500 m
has shown that the biomass of demersal decapods
was 48268, 17440 and 4376 g km
2
respectively
(Company
et al., 2004).
The low-diversity, low-density Levantine deep
water fauna has long been presumed to be the poor-
est in the Mediterranean (Fredj, 1974). It was recog-
nised that the scanty data may be due to sparse
research efforts, that the “the different parts of the
deep Mediterranean have not been equally sampled”
(Fredj and Laubier, 1985), and that a particularly
“limited amount of sampling [was] carried out in the
eastern basins” (Bellan-Santini, 1990). It was even
suggested that “[t]he relative species richness of …
faunas of the different sectors of Mediterranean is
better correlated with the level of research effort
than the true species richness” (Bellan-Santini,
1990). As late as 1989 it was still possible for
Klausewitz to wonder “whether an ecological or a
geographical factor may be the reason for this limit-
ed distribution or whether the low number of zoo-
logical resp. [sic] oceanographical stations and
research ships in the eastern half of the
Mediterranean provides the reason for the lack of
records.” However, considering the sampling effort,
the diverse gear used and the extended period of
sampling, we may assume that the low number of
species and specimens recorded does not stem sole-
ly from selective or inefficient gear, and is unlikely
to increase much with additional surveys using sim-
ilar sampling gear, though the number may be aug-
mented by using other sampling methods.
Bathymetric distribution of the Levantine
deep water fauna
As early as 1893 Marenzeller reported that
species occur deeper in the Levant than elsewhere in
the Mediterranean. Marenzeller’s records were con-
sidered suspect, an artefact resulting from a “sys-
tematic mistake on the depth measurements” that
“needs to be cleared up in the future” (Fredj and
Laubier, 1985: 128). Recent studies published
greater depth records in the Levantine Sea than in
the western Mediterranean for 14 serpulid species,
with a third of the depth extensions > 400 m (Ben
Eliahu and Fiege, 1996). Twenty-two fish species
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