Preprint volume - SIBM

Pre-print Volume –Posters
NECTON AND FISHERY COMMITEE
D. CUCCU, M. MEREU, P. MASALA, A. CAU, P. JEREB*
Department of Animal Biology and Ecology, University of Cagliari, Via T. Fiorelli, 1 – 09126 Cagliari, Italy.
cuccu@unica.it
*ISPRA ex-ICRAM, Roma, Italy.
FIRST RECORD OF STOLOTEUTHIS LEUCOPTERA
(CEPHALOPODA: SEPIOLIDAE) IN THE SARDINIAN WATERS
PRIMO RINVENIMENTO DI STOLOTEUTHIS LEUCOPTERA
(CEPHALOPODA: SEPIOLIDAE) NELLE ACQUE SARDE
Abstract – Morphometric and meristic data of two mature females of Stoloteuthis leucoptera
(Cephalopoda: Sepiolidae) from the Sardinian waters are reported. These are the first records of the
species in the Sardinian seas and they add important information to our still poor knowledge on the species
in the Mediterranean Sea.
Keywords: Stoloteuthis leucoptera, Mediterranean Sea, Sardinian seas, bottom trawling, fishery surveys.
Introduction - The leucoptera bobtail squid, Stoloteuthis leucoptera (Verril, 1878), is
distributed in the Western Atlantic Ocean from the Gulf of St Lawrence to the Straits
of Florida and in the Eastern Atlantic, in the Bay of Biscay and in the Benguela Current
off Namibia (Reid and Jereb, 2005). Only a few records exist for the Mediterranean
Sea, where the species may be of recent introduction (Orsi Relini and Massi, 1991). As
for the Italian waters, S. leucoptera was caught in the Ligurian Sea, in the northern and
southern Tyrrhenian Sea and off the Gorgona Island (Reid and Jereb, 2005). Here, the
first findings of the species in the Sardinian waters are reported and some
morphometric and meristic data are presented.
Materials and methods - Stoloteuthis leucoptera specimens were collected during the
scientific trawl surveys MEDITS (Bertrand et al., 2000) and GRUND (Relini, 1998)
carried out in the Sardinian waters during summer 2005 and winter 2007, respectively.
Fresh specimens were measured (ML, to the nearest 1 mm) and weighted (TW, to the
nearest 0.01 g); sex was determined and maturity stages were established using a 3
stages maturity scale (Bertrand et al., 2000). Measurements and abbreviations used are
those given in Roper and Voss (1983). The mandibles were removed and for each one,
the upper crest (UCL), upper hood (UHL), upper rostral (URL), lower crest (LCL),
lower hood (LHL) and lower rostral (LRL) measurements were taken (Clarke, 1986).
Oocytes and spermatangia were measured along their major axis.
Results - Two specimens of S. leucoptera (ML: 10.4 and 14.5 mm) were recorded, in
the north-eastern Sardinian waters (N41°12,720' E9°55,880'-N41°12,830' E9°55,800')
at a mean depth of 550 meters, and in the Gulf of Cagliari (N39°08,020' E9°20,780'-
N39°06,800' E9°24,000') at 360 meters, along with other sepiolids. Both were mature
females; their mantle cavity was filled mostly by the ovary and the white creamy
nidamental glands. Oocytes in the ovary were reticulate and ranged in length between
0.1 and 3.5 mm; oocytes in the oviducts were smooth, their size ranging between 3.5
and 3.8 mm. Six spermatangia of about 0.5 mm length were found on one female (ML
14.2 mm), embedded in the tissue above the left eye. Main morphometric and meristic
data of the two specimens are given in Tab. 1.
41 st S.I.B.M. CONGRESS Rapallo (GE), 7-11 June 2010
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