234
MALQOLM R. CLARKE
1. Taonius megalops (Prosch, 1849)
Owenia megabps PTosch, 1849
Cranchia megabps Morch, 1850
Leachia hyperborea Steenstrup, 1856
Taoniua hyperboreus Steenstrup, 1861
Desmoteuthis tenera Verrill, 1882a
I;oligopsia hyperborea Rochebrune, 1884
D m t e u t h i s hyperborea Pfeffer, 1900
Teuthowenia megabps Chun, 1910a
Megalocranchia hyperborea Berry, 1912a
Desmoteuthis megalops Muus, 1956
Megalocranchia megabps Voss, 1960a
Taonius megalops Clarke, 1962d
Degner (1925) and then Muus (1956) studied the changes in growth
of this species and were able to synonymize a number of species based
on growth stages. The species (Fig. 50) has been recorded from west
and south Greenland (Steenstrup, 1856; Mbrch, 1857; Jeffreys, 1876;
Posselt, 1898; Grimpe, 1933; MUUS, 1962; Nesis, 1965), off the eastern
coast of the United States (Verrill, 1882a; Hoyle, 1886a; Voss, 1960a),
off Iceland and the Faroes (Prosch, 1849; Mbrch, 1867; Russell, 1909,
1922; Degner, 1925; Nielsen, 1930; Bruun, 1945), Jan Mayen (F'riele,
1879 after Grimpe, 1933), west of the British Isles (Steenstrup, 1861;
Hoyle, 1886a; Massy, 1909, 1913; Degner, 1925; Stephen, 1944), in
the Bay of Biscay (Hoyle, 1906b; Chun, 1913; Degner, 1925), off the
Azores (Chun, 1913; Joubin, 1920), in the eastern North Atlantic
(Pfeffer, 1912; Chun, 1913; Joubin, 1920,1924; Degner, 1925) and south
to 1"N (Pfeffer, 1912). It does not apparently occur in the Mediterranean. There is one record from western Canada (Clarke, 1962b).
It has been caught at the surface (Hoyle, 1886a; Massy, 1913) and
in an open net fished to 4 500 m (Joubin, 1924). Degner (1925) found
that 25% of specimens, representing 2.3 per haul, were taken at less
than 30 m (65 m of wire out), 52% of specimens, representing 2 per
haul were taken at 30-150 m (65-300 m of wire out) and 23% of
specimens, representing 1.8 per haul were taken at more than 150 m
(more than 300 m of wire out). Joubin (1933) considered that adults
were only found at great depths (2 000-3 300 m) but there is little
evidence to support this.
Growth changes in form and the photophores on the eye bulb have
been traced by Degner (1925) and Muus (1956). The largest specimen
has a mantle length of 21.0 cm (Steenstrup, 1861a); very few have been
sexed and there are seldom comments on their sexual maturity.
Small larvae are present in both January and July off southern
MALQOLM R. CLARKE
1. Taonius megalops (Prosch, 1849)
Owenia megabps PTosch, 1849
Cranchia megabps Morch, 1850
Leachia hyperborea Steenstrup, 1856
Taoniua hyperboreus Steenstrup, 1861
Desmoteuthis tenera Verrill, 1882a
I;oligopsia hyperborea Rochebrune, 1884
D m t e u t h i s hyperborea Pfeffer, 1900
Teuthowenia megabps Chun, 1910a
Megalocranchia hyperborea Berry, 1912a
Desmoteuthis megalops Muus, 1956
Megalocranchia megabps Voss, 1960a
Taonius megalops Clarke, 1962d
Degner (1925) and then Muus (1956) studied the changes in growth
of this species and were able to synonymize a number of species based
on growth stages. The species (Fig. 50) has been recorded from west
and south Greenland (Steenstrup, 1856; Mbrch, 1857; Jeffreys, 1876;
Posselt, 1898; Grimpe, 1933; MUUS, 1962; Nesis, 1965), off the eastern
coast of the United States (Verrill, 1882a; Hoyle, 1886a; Voss, 1960a),
off Iceland and the Faroes (Prosch, 1849; Mbrch, 1867; Russell, 1909,
1922; Degner, 1925; Nielsen, 1930; Bruun, 1945), Jan Mayen (F'riele,
1879 after Grimpe, 1933), west of the British Isles (Steenstrup, 1861;
Hoyle, 1886a; Massy, 1909, 1913; Degner, 1925; Stephen, 1944), in
the Bay of Biscay (Hoyle, 1906b; Chun, 1913; Degner, 1925), off the
Azores (Chun, 1913; Joubin, 1920), in the eastern North Atlantic
(Pfeffer, 1912; Chun, 1913; Joubin, 1920,1924; Degner, 1925) and south
to 1"N (Pfeffer, 1912). It does not apparently occur in the Mediterranean. There is one record from western Canada (Clarke, 1962b).
It has been caught at the surface (Hoyle, 1886a; Massy, 1913) and
in an open net fished to 4 500 m (Joubin, 1924). Degner (1925) found
that 25% of specimens, representing 2.3 per haul, were taken at less
than 30 m (65 m of wire out), 52% of specimens, representing 2 per
haul were taken at 30-150 m (65-300 m of wire out) and 23% of
specimens, representing 1.8 per haul were taken at more than 150 m
(more than 300 m of wire out). Joubin (1933) considered that adults
were only found at great depths (2 000-3 300 m) but there is little
evidence to support this.
Growth changes in form and the photophores on the eye bulb have
been traced by Degner (1925) and Muus (1956). The largest specimen
has a mantle length of 21.0 cm (Steenstrup, 1861a); very few have been
sexed and there are seldom comments on their sexual maturity.
Small larvae are present in both January and July off southern