48
THE BIOLOGY OF EUPHAUSIIDS
below 700 m during the day, usually deeper than T . monacantha and
T . orientalis, and performs a diurnal vertical migration. Attains a
maximum length of about 44 mm. (Ortmann, 1893 ; Hansen, 1905a,b,
1915, 1916; Tattersall, 1912a, 1939; Illig, 1930; Leavit,t, 1935, 1938;
Ruud, 1936; Boden, 1954; Brinton, 1962a; Grindley and Penrith, 1965 ;
Nemoto, 1965; Roger, 1966, 196713).
Thysanopoda orientalis Hansen, 1910
T. orientalis Hansen, 1910: 85-87, pl. xiii, fig. 2, a-i; 1912, 222-223, pl. v,
This is a mesopelagic species (Fig. 14). Atlantic: recorded from
western area, Bermuda to Florida and Gulf of Mexico but not from
eastern Atlantic except off South Africa. Pacific: its northern and
southern limits of distribution are bounded by those of T. acutifrons
near 40"N and 40"s. It has nearly the same geographical range as
T . pectinata and T . monacantha, bounded in the north by the 10°C
isotherm a t 100m and to the south by the 9°C isotherm at 200ni.
Indian : present in Straits of Mozambique and northwards between
about 10"N and 10"s. Adults below 280 m during the day; performs a
diurnal vertical migration. Attains a maximum length of about 38 mm.
(Hansen, 1915, 1916; Torelli, 1934; Leavitt, 1935, 1938; Tattersall,
1939 ; Lebour, 1950; Boden, 1954; Brinton, 1962a; Ponomareva, 1963,
1964; Grindley and Penrith, 1965; Nemoto, 1965; Roger, 1967b).
fig. 2, a-i; Boden et ul., 1955: 309-311, fig. 12.
Thysanopoda microphthalma G. 0. Sars, 1885
T. microphthalma G. 0. Sars, 1885 : 106-108, fig. 3 ; (nec Lo Bianco, 1903 :
T . distinguendu Hansen, 190th: 17-18, fig. 13 (Jide Sheard, 1942: 61);
T . microphthalma occurs in the Atlantic and Indian Oceans but not
in the Pacific (Fig. 14). It has been recorded west of Ireland but all
other records are from between 35"N and 40"s. Not present in Mediterranean. Probably deep oceanic form. (Sars, 1885 ; Ortmann, 1893 ;
Hansen, 1905a; Tattersall, 1912a, 1927; Illig, 1930; Ruud, 1936;
Boden, 1954).
192).
Holt and Tattersall, 1906a: 11, pl. ii.
Thysanopoda acutifrons Holt and Tattersall, 1905
T . ucutifrons Holt and Tattersall, 1905a: 102-103 ; 1906a : 8-11, pl. i ; Hansen,
1910: 85-86; Einarsson, 1945: 16-21, 39-41, figs. 4-7, 14: Boden et al., 1955:
311-313, fig. 13. T. pectinuta, Hansen, 1905a : 16-17, fig. 12 ; (nec Ortmann, 1893 :
10; nec Hansen, 1905b: 25). T. johnstoni Sheard, 1942: 63-64, figs. A-Q;
Sheard; 1953 : 10-11 (Jide Brinton, 1962a : 89-90). T . dubia Banner, 1950 : 9-13,
pl. i, figs. 20, a+, pl. ii, figs. 20, d-h (Jide Brinton, 1962a: 89).
THE BIOLOGY OF EUPHAUSIIDS
below 700 m during the day, usually deeper than T . monacantha and
T . orientalis, and performs a diurnal vertical migration. Attains a
maximum length of about 44 mm. (Ortmann, 1893 ; Hansen, 1905a,b,
1915, 1916; Tattersall, 1912a, 1939; Illig, 1930; Leavit,t, 1935, 1938;
Ruud, 1936; Boden, 1954; Brinton, 1962a; Grindley and Penrith, 1965 ;
Nemoto, 1965; Roger, 1966, 196713).
Thysanopoda orientalis Hansen, 1910
T. orientalis Hansen, 1910: 85-87, pl. xiii, fig. 2, a-i; 1912, 222-223, pl. v,
This is a mesopelagic species (Fig. 14). Atlantic: recorded from
western area, Bermuda to Florida and Gulf of Mexico but not from
eastern Atlantic except off South Africa. Pacific: its northern and
southern limits of distribution are bounded by those of T. acutifrons
near 40"N and 40"s. It has nearly the same geographical range as
T . pectinata and T . monacantha, bounded in the north by the 10°C
isotherm a t 100m and to the south by the 9°C isotherm at 200ni.
Indian : present in Straits of Mozambique and northwards between
about 10"N and 10"s. Adults below 280 m during the day; performs a
diurnal vertical migration. Attains a maximum length of about 38 mm.
(Hansen, 1915, 1916; Torelli, 1934; Leavitt, 1935, 1938; Tattersall,
1939 ; Lebour, 1950; Boden, 1954; Brinton, 1962a; Ponomareva, 1963,
1964; Grindley and Penrith, 1965; Nemoto, 1965; Roger, 1967b).
fig. 2, a-i; Boden et ul., 1955: 309-311, fig. 12.
Thysanopoda microphthalma G. 0. Sars, 1885
T. microphthalma G. 0. Sars, 1885 : 106-108, fig. 3 ; (nec Lo Bianco, 1903 :
T . distinguendu Hansen, 190th: 17-18, fig. 13 (Jide Sheard, 1942: 61);
T . microphthalma occurs in the Atlantic and Indian Oceans but not
in the Pacific (Fig. 14). It has been recorded west of Ireland but all
other records are from between 35"N and 40"s. Not present in Mediterranean. Probably deep oceanic form. (Sars, 1885 ; Ortmann, 1893 ;
Hansen, 1905a; Tattersall, 1912a, 1927; Illig, 1930; Ruud, 1936;
Boden, 1954).
192).
Holt and Tattersall, 1906a: 11, pl. ii.
Thysanopoda acutifrons Holt and Tattersall, 1905
T . ucutifrons Holt and Tattersall, 1905a: 102-103 ; 1906a : 8-11, pl. i ; Hansen,
1910: 85-86; Einarsson, 1945: 16-21, 39-41, figs. 4-7, 14: Boden et al., 1955:
311-313, fig. 13. T. pectinuta, Hansen, 1905a : 16-17, fig. 12 ; (nec Ortmann, 1893 :
10; nec Hansen, 1905b: 25). T. johnstoni Sheard, 1942: 63-64, figs. A-Q;
Sheard; 1953 : 10-11 (Jide Brinton, 1962a : 89-90). T . dubia Banner, 1950 : 9-13,
pl. i, figs. 20, a+, pl. ii, figs. 20, d-h (Jide Brinton, 1962a: 89).