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fishery catches in the Aeolian islands (Battaglia et al.,       lack of records and further information on the population
2010), O. bartramii is less abundant than the european          of the species in the given area precludes an assessment
flying squid, T. sagittatus, in the Mediterranean Sea.          beyond Data Deficient at this time (Amorim et al., 2009
                                                                and references therein). Up to date, it has never been
1.2. The first record of the bigeye thresher shark, Alopias     recorded in the Adriatic, which also complies with the
    superciliosus (Elasmobranchii: Lamniformes:                 most recent review of shark species that have previously
    Alopiidae) in the Adriatic Sea                              been recorded in the basin (Gajić, 2015). The only spe-
                                                                cies of the genus Alopias known to be native in the area
By F. Madiraca and B. Davidov                                   up till now was the common thresher shark, A. vulpinus
                                                                (Bonnaterre, 1788) (Gajić, 2015). It is also possible that
    On the 20th of May 2012, a bigeye thresher shark,           A. superciliosus does occur in the Adriatic but is con-
Alopias superciliosus (Lowe, 1841) was caught by a lo-          fused with A. vulpinus.
cal fisherman, in the proximity of the island of Mamula
(42.3953°N, 18.5583°E) in Montenegro (eastern coast of          Fig. 3: Edited photographic evidence of the landed shark with
the Adriatic) (Fig. 2). Even though the exact location is       highlighted morphological features used for identification of the
unknown, it was noted that the capture occurred 15 Nm           bigeye thresher shark, Alopias supercilliosus: position of the
from the mentioned island. According to the report that         first dorsal fin in relation to the trailing end of the pectoral fins
provided information about the capture, published in the        (red lines), presence of the prominent lateral groove (red arrow)
Vijesti online newspaper, the specimen measured 485 cm          and relatively big eye (red circle); photo: Kosić, 2012; edited.
(total length) and weighed 285 kg (Kosić, 2012). In order
to identify the species, the authors examined photograph-
ic evidence of the capture.

    The three main observed identification features in the
analysis were: (1) relative distance between the leading
point of the first dorsal fin and the trailing end of the pec-
toral fins (Tricas et al., 1997), (2) presence of relatively
big eyes facing upwards, (3) existence of prominent lat-
eral grooves that start between and just behind the men-
tioned big eyes (Compagno, 2001) (Fig. 3).

    Alopias superciliosus is circumglobal in tropical and
temperate seas (Compagno, 2001) and is considered to
be a highly migratory species. It is caught as bycatch of
the semi-industrial fisheries in the western and central
Mediterranean. In recent years a records from the eastern
basin have also increased (off Israel in the Levantine ba-
sin, in the Aegean Sea off Turkey and southern Greece,
and off southern Crete) (Amorim et al., 2009 and refer-
ences therein). Unfortunately, it is poorly documented in
the Mediterranean and is considered scarce or rare. The

Fig. 2: The island of Mamula (42.3953°N, 18.5583°E), Montenegro (red circle); image created with Google Maps platform (position in
the Adriatic: see top left corner).

474	 Medit. Mar. Sci., 16/2, 2015, 472-488
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