REVIEW OF THE SYSTEMATICS AND ECOLOGY O F OCEANIC SQUIDS
119
1. Illex illecebrosus (Lesueur, 1821)
Loligo illecebrosus Lesueur, 1821
Ommastrephes illecebrosus, Verrill, 1880c
In the western North Atlantic (Fig. lo), the species has been
recorded at Frederikshaab, Greenland (Posselt, 1898), Hebron harbour,
Labrador (Squires, 1957, 1959), off Newfoundland (Lesueur, 1821;
Verrill, 1882c; Williams, 1909; Frost and Thompson, 1932, 1933, 1934;
Boone, 1933; Squires, 1957; Anon, 1958), Cape Hatteras (Verrill, 1882c),
Nova Scotia (Boone, 1933), Trois Pistoles, Quebec (Prbfontaine and
Brunel, 1962), eastern United States (Frost and Thompson, 1932),
Caribbean and Gulf of Mexico (Voss, 1955, 1956a, 1956b). The northern distribution has been said to include Iceland (Bardarson, 1919;
Bruun, 1945), the Faroes (Grimpe, 1933) and northern Europe (Pfeffer,
1908b, 1912; Voss, 1956b). Because of the confusion with I . coindeti
in this region the exact extent of distribution is not known. However,
there is some reason to doubt Bruun’s record for Iceland which was
based on a note by Grnrndal which could have referred to
I . coindeti and a short passage in Murray and Hjort (1912) “Illex
illecebrosus and Omrnatostrephes todarus are northern forms, of great
importance on the banks of Newfoundland, and along the coasts of
Iceland and Norway”. Bruun understood this to mean that both
species are important on both sides of the North Atlantic, but it seems
much more likely that the authors meant that I . illecebrosus was
important on the western and 0. sagittatus ( = O . todarus) on the
eastern side of the northern Atlantic; particularly as the latter species
is not found on the western side. Other doubtful records are Joubin’s
(1920) from the Bay of Biscay and Chun’s (1913) from north west
Africa and the Canary Islands, all of which could have referred to
I . coindeti. In view of the doubt regarding the extension of I . illecebrosus
to Iceland and the Faroes, workers have sometimes been tempted
into considering the species of the two sides of the Atlantic as distinct
forms, but Adam (1952), by a statistical analysis of dimensions, has
shown the situation to be much more complex. He found that specimens from the Bristol Channel were intermediate between I . illecebrosus
and I . coindeti, but that they were closer to the former; he also found
that, of the Illex appearing in the North Sea, those caught in June
resembled I . coindeti, and females caught in March and May were close
to I . illecebrosus. Although I . illecebrosus is most numerous near to
coasts and probably lives on the upper slope and shelf, a damaged
juvenile (tentatively identified as this species) has been recorded
rather far from land (Joubin, 1895b). A record from Onondaga Lake
A . M . B . 4
0
119
1. Illex illecebrosus (Lesueur, 1821)
Loligo illecebrosus Lesueur, 1821
Ommastrephes illecebrosus, Verrill, 1880c
In the western North Atlantic (Fig. lo), the species has been
recorded at Frederikshaab, Greenland (Posselt, 1898), Hebron harbour,
Labrador (Squires, 1957, 1959), off Newfoundland (Lesueur, 1821;
Verrill, 1882c; Williams, 1909; Frost and Thompson, 1932, 1933, 1934;
Boone, 1933; Squires, 1957; Anon, 1958), Cape Hatteras (Verrill, 1882c),
Nova Scotia (Boone, 1933), Trois Pistoles, Quebec (Prbfontaine and
Brunel, 1962), eastern United States (Frost and Thompson, 1932),
Caribbean and Gulf of Mexico (Voss, 1955, 1956a, 1956b). The northern distribution has been said to include Iceland (Bardarson, 1919;
Bruun, 1945), the Faroes (Grimpe, 1933) and northern Europe (Pfeffer,
1908b, 1912; Voss, 1956b). Because of the confusion with I . coindeti
in this region the exact extent of distribution is not known. However,
there is some reason to doubt Bruun’s record for Iceland which was
based on a note by Grnrndal which could have referred to
I . coindeti and a short passage in Murray and Hjort (1912) “Illex
illecebrosus and Omrnatostrephes todarus are northern forms, of great
importance on the banks of Newfoundland, and along the coasts of
Iceland and Norway”. Bruun understood this to mean that both
species are important on both sides of the North Atlantic, but it seems
much more likely that the authors meant that I . illecebrosus was
important on the western and 0. sagittatus ( = O . todarus) on the
eastern side of the northern Atlantic; particularly as the latter species
is not found on the western side. Other doubtful records are Joubin’s
(1920) from the Bay of Biscay and Chun’s (1913) from north west
Africa and the Canary Islands, all of which could have referred to
I . coindeti. In view of the doubt regarding the extension of I . illecebrosus
to Iceland and the Faroes, workers have sometimes been tempted
into considering the species of the two sides of the Atlantic as distinct
forms, but Adam (1952), by a statistical analysis of dimensions, has
shown the situation to be much more complex. He found that specimens from the Bristol Channel were intermediate between I . illecebrosus
and I . coindeti, but that they were closer to the former; he also found
that, of the Illex appearing in the North Sea, those caught in June
resembled I . coindeti, and females caught in March and May were close
to I . illecebrosus. Although I . illecebrosus is most numerous near to
coasts and probably lives on the upper slope and shelf, a damaged
juvenile (tentatively identified as this species) has been recorded
rather far from land (Joubin, 1895b). A record from Onondaga Lake
A . M . B . 4
0