Page 10 - BALSAMO_etalii_1996

M . BALSAMO, E. FREGNI, P. TONGIORGI
Genus Heterolepidoderma Remane, 1926
Heterolepidoderma loricatum Schrom, 1972
S. Vito lo Capo, 1-2 m; Punta Braccetto, 1-2 m; Pozzallo, 1-2 m;
Rada di Porto Palo, 2-3 m.
The species is widely present in Italy along the penin-
sular (Liguria, Tuscany, Latiurn, Carnpania, Apulia, the
Marches and Veneto) and island (the Tuscan archipela-
go, the island of Ponza, the island of Ischia, Sardinia)
coasts.
Farnily XENOTRICHULIDAE Remane, 1927
Genus Heteroxenotricbula Wilke, 1954
Heteroxenotrichula squamosa Wilke, i 954
Trappeto, 2-3 m; Porto Palo, littoral; Punta Bmccetto, 1-2 m; Lido species to the Italian peninsular coast and to the island of
Arenella. 1-2 m; Giardini Naxos, 2-3 m; Jesi, 1-2 m; S. Ambrogio, 2-3 Procida (Hummon et al., 1996)and are reported here for
m; S. Vito lo Capo, 1-2 m.
In Italy, the species was reported from Liguria,
Tuscany (coast and archipelago), Latium, Campania, the
island of Ischia, the Ionian coasts of Calabria, Lucania,
Apulia, and Sardinia.
Genus Xenotrichula Remane, 1927
Xenotrichula intermedia Remane, 1927
Lido Signorino, 2-3 m; Porto Palo. 1-2 m: Agrigento, 1 m; Punta
Braccetto, 1-2 m; Manfria, 2-3 m.
Xenotrichula intermedia is a cosmopolite species
present in numerous localities along the peninsular
coastline, at the Tuscan archipelago and in Sardinia. The
single specimen from Punta Braccetto showed two
cerebral eyes, a feature never mentioned in the descrip-
tions of this species.
DISCUSSION
Gastr~trichfauna from Sicily is composed of a number
of species, 41, which is comparable with that found in
some minor islands, like Capraia (36) and Elba (45) in the
Tuscan archipelago (Balsamo et al., 1992; Todaro e1 al.,
1992), but is lower than the number of species from the
other Italian rnajor island, Sardinia (55) (Balsamo et al.,
1995).
The lower faunistic richness of Sicily compared with
Sardinia could be related to the greater granulometric
hornogeneity of its sediments, rnainly cornposed of fine
(56%) and mediurn sand (29%), as well as to the poorer
variety of the coastal environrnents; even the bad con-
dition of the sea at the sampling time may have had some
influente in lowering the number of species found.
The 35% of the localities shows a number of species
ranging between 6 and 15. Only two sites stand out from
the others, Cefalù with 17 species (1989) and Giardini
Naxos with 19 species (1994), while most localities show
less than 6 species each. On the whole, the biodiversity
of al1 the sites appears quite low and the fauna poorly
diverse. The eastern coast of Sicily, in spite of less
numerous samplings carried out, revealed a number of
species sirnilar to that of the other coast traits, mainly due
to the greater faunistic richness of the sediment from
Giardini Naxos.
Only one macrodasyid (Tetrancbyroderma sp.) of the
41 species found could not be identified. The presence
of Tetrancbyroderma anomalopsum, T. polyprobo-
lostomum, T. kontosomum and T. tanymesatberum is of
interest, since they have recently been described as new
the second time; T. anomalopsum is recorded for the fir-
st tirne in the Tyrrhenian sea. The occurrence of both
species of the genus Thaumastodemza known for Italy
(T. mediterraneum and T. ramuliferum) is noteworthy,
as it is the finding of the Chaetonotus species previously
described by Valbonesi & Luporini (1987) from the
Somalian coast, and recently found again by us in sam-
ples from Tuscan coast (Punta Ala), Red Sea (Sharrn E1
Sheik) and Easter Mediterranean Sea (Larnaka Bay, island
of Cyprus).
Three macrodasyid (Paraturbanella dohrni, I? teis-
sieri, Turbanella ambronensis) and three chetonotid
species (Chaetonotus dispar, C. lacunosus and
Heterosenolricbula squamosa), known for their wide
geographic distribution, have also been collected along
the whole coast of Sicily. Most species found in Sicily
(92.8%) have been recorded along the peninsular coast
and at minor islands, thus proving a remarkable similarity
in the composition of Italian gastrotrich communities.
REFERENCES
Balsamo A l . , Fregni E.. Tongiorgi P,, 1994 - Marine and freshwater
Gastrotricha from the island of Montecristo (Tuscan archipelago,
Italy), with the description of new species. Boll. Zoll., 61:
217-227.
Balsamo hl., Fregni E., Tongiorgi P,, 1995 -Marine Gastrotricha from
the coasts of Sardinia (Italy). Boll. Zool., 62: 273-286.
Balsamo M., Todaro M. A,, Tongiorgi P., 1992 - Marine gastrotrichs
from the Tuscan Archipelago (Tyrrhenian Sea). Il. Chaetonotida,
with description of three new species. Boll. Zool., 59: 487-498.
Evans W. A,, Todaro M. A., Hummon W. D., 1993 - Eutrophication
and gastrotrich diversity in the Northern Adriatic Sea. blar.
Pollut. Bull., 26: 268-272.
Giere O.! Eleftheriou A., Murison D. J., 1988 - Abiotic factors. In: R.
Higgins 8i H. Thiel (eds), Introducrion to the study of meiofauna.
Smithsonian Institution Press. Washington, pp. 61-78.
Hummon W. D., Balsamo M., Todaro M. A,, I992 - Italian marine
Gastrotricha: 1. Six n e w and o n e redescribed species of
Chaetonotida. Boll. Zoll., 59: 499-516.
Hummon W. D,, Todaro M. A,, Tongiorgi P., 1993 - Italian marine
Gastrotricha: Il. One new genus and ten new species of
Macrodasyida. Boll. Zoll., 60: 109-127.