98
THE BIOLOGY O F EUYHAUSIIDS
36' 50" 68"52'W in the western Atlantic.
1935, 1938; Brinton, 1962a.)
(Hansen, 1910 ; Leavitt,
Xtylocheiron elongatum G. 0. Sars, 1883
S. elongaturn G. 0. Saw, 188313: 32-33; 1885: 146-147, pl. xxvii, figs. 6-10;
This mesopelagic species belongs to the "Xtylocheiron longicorne
group ) ) of species and is present in the Atlantic, Pacific and Indian
Oceans (Fig. 32). Atlantic : most commonly present between about
40"N and 40"s but occasional individuals have been found as far north
as southern Iceland ; it is not present in the Mediterranean. Pacific :
found between 40°N and 35"s but more widespread in the western than
the eastern Pacific; absent from the northern part of the California
Current and from the Eastern Equatorial Basin except in the latitudes
of the Equatorial Countercurrent (3" to 9"N), and also absent from the
northern part of the Peru Current and westwards beyond the Galapagos
Islands. Indian : present between about 12"N and 30'5, in the Red Sea
but not in the northern regions of the Arabian Sea nor the Gulf of
Oman. This species lives a t greater depths than the other species in the
"Xtylocheiron longicorne group " ; usually between 100 and 500 m
depth. Length: males up to 13 mm, females up to 16 mm. (Sars,
1885; Ortmann, 1893; Hansen, 1905a, 1915; Tattersall, 1911, 1912a,
1927, 1936c, 1939; Illig, 1930; Leavitt, 1935, 1938; Ruud, 1936;
Einarsson, 1945; Fraser, 1950, 1956, 1961; Lebour, 1950; Boden, 1954,
1961a; Lewis, 1954; Nepgen, 1957; Dahl, 1961; Brinton, 1962a;
Ponomareva, 1963, 1968 ; Roger, 1967b.)
Bodon et al., 1955: 386-388, fig. 52.
Xtylocheiron indicum Silas and Mathew, 1967
S. indicus Silas and Mathew, 1967 : 169-172, fig. 1.
This species closely resembles S. elongatum and has so far only been
recorded from the west coast of India near l0"N 76OE (Fig. 32). Length
12-14 mm. (Silas and Mathew, 1967.)
Xtylocheiron longicorne G. 0. Sars, 1883
S. Zongicorne G. 0. Sars, 1883b : 32 ; 1885 : 144-145, pl. xxvii, fig. 5 ; Hansen,
1910: 120-121, pl. xvi, fig. 5, a-b; 1912: 279-280, pl. xi, fig. 4, a-b; Banner,
1950 : 37-38, pl. iv, fig. 25a ; Boden et al., 1955 : 388-389, fig. 53. S . mastigophorum
Chun, 1887 : 30 (partim).
This species along with the related species S. afine, S. suhmii,
8. microphthalma, S. insulare, and X. elongatum form the "Xtylocheiron
longicorne group '' of species. S. longicorne is a mesopelagic species
THE BIOLOGY O F EUYHAUSIIDS
36' 50" 68"52'W in the western Atlantic.
1935, 1938; Brinton, 1962a.)
(Hansen, 1910 ; Leavitt,
Xtylocheiron elongatum G. 0. Sars, 1883
S. elongaturn G. 0. Saw, 188313: 32-33; 1885: 146-147, pl. xxvii, figs. 6-10;
This mesopelagic species belongs to the "Xtylocheiron longicorne
group ) ) of species and is present in the Atlantic, Pacific and Indian
Oceans (Fig. 32). Atlantic : most commonly present between about
40"N and 40"s but occasional individuals have been found as far north
as southern Iceland ; it is not present in the Mediterranean. Pacific :
found between 40°N and 35"s but more widespread in the western than
the eastern Pacific; absent from the northern part of the California
Current and from the Eastern Equatorial Basin except in the latitudes
of the Equatorial Countercurrent (3" to 9"N), and also absent from the
northern part of the Peru Current and westwards beyond the Galapagos
Islands. Indian : present between about 12"N and 30'5, in the Red Sea
but not in the northern regions of the Arabian Sea nor the Gulf of
Oman. This species lives a t greater depths than the other species in the
"Xtylocheiron longicorne group " ; usually between 100 and 500 m
depth. Length: males up to 13 mm, females up to 16 mm. (Sars,
1885; Ortmann, 1893; Hansen, 1905a, 1915; Tattersall, 1911, 1912a,
1927, 1936c, 1939; Illig, 1930; Leavitt, 1935, 1938; Ruud, 1936;
Einarsson, 1945; Fraser, 1950, 1956, 1961; Lebour, 1950; Boden, 1954,
1961a; Lewis, 1954; Nepgen, 1957; Dahl, 1961; Brinton, 1962a;
Ponomareva, 1963, 1968 ; Roger, 1967b.)
Bodon et al., 1955: 386-388, fig. 52.
Xtylocheiron indicum Silas and Mathew, 1967
S. indicus Silas and Mathew, 1967 : 169-172, fig. 1.
This species closely resembles S. elongatum and has so far only been
recorded from the west coast of India near l0"N 76OE (Fig. 32). Length
12-14 mm. (Silas and Mathew, 1967.)
Xtylocheiron longicorne G. 0. Sars, 1883
S. Zongicorne G. 0. Sars, 1883b : 32 ; 1885 : 144-145, pl. xxvii, fig. 5 ; Hansen,
1910: 120-121, pl. xvi, fig. 5, a-b; 1912: 279-280, pl. xi, fig. 4, a-b; Banner,
1950 : 37-38, pl. iv, fig. 25a ; Boden et al., 1955 : 388-389, fig. 53. S . mastigophorum
Chun, 1887 : 30 (partim).
This species along with the related species S. afine, S. suhmii,
8. microphthalma, S. insulare, and X. elongatum form the "Xtylocheiron
longicorne group '' of species. S. longicorne is a mesopelagic species