11. ECOLOGY OF DISTRIBUTION
345
existent in this area. Ponomareva found that E. diomedeae, E. brevis,
and, a t one station, Stylocheiron carinatum were the commonest species.
The biomass of euphausiids is considerably less in the Bay of Bengal
than in the Arabian Sea. Pseudeuphausia latifrons is the dominant
species in the Andaman See. Ponomareva lists Nematoscelis atlantica
as present in the Arabian Sea but does not mention it as remarkable.
Stylocheiron indicum, a new species, has so far only been recognized in
samples off western India (Silas and Mathew, 1967).
Antarctic Ocean
There are twelves species of euphausiids that have circumpolar
distributions in the Antarctic.
Off Antarctic coastlines
Euphausia crystallorophias.
Extending from Antarct'ic coast t o Antarctic Convergence (50"s60"s)
Euphausia superba; Thysanoessa mucrura.
Extending from ice edge to Antarctic Convergence
Euphausia frigida; Thysanobsa vicina.
Antarctic Convergence
Euphausia triacantha.
Antarctic Convergence to Subtropical Convergence
Euphausia vallentini, E. sirnilis, E. longirostris.
Southern regions of subtropical water
Euphausia lucens, E. similis var. armuta, E. spinifera.
The distribution of euphausiids in the Antarctic is still not absolutely
clear. Euphausia crystallorophias is a neritic species living under the
ice along the edge of the Continent. The large Euphausia superba lives
close to the ice edge and probably to a large extent under the ice, but
also extends northwards to the Antarctic Convergence, while E . frigida
occurs between the ice edge and the Antarctic Convergence. Baker
(1959) has shown that the populations of E. triacantha are intimately
associated with the Antarctic Convergence. The three species, E.
vallentini, E . similis, and E. longirostris are subantarctic species although
E . similis extends northwards to the Subtropical Convergence. The
related species, E. similis var. armata, according to Baker (1965) lives
north of the Subtropical Convergence but penetrates subantarctic
water. John (1936) classifies E . lucens as a subantarctic species but
345
existent in this area. Ponomareva found that E. diomedeae, E. brevis,
and, a t one station, Stylocheiron carinatum were the commonest species.
The biomass of euphausiids is considerably less in the Bay of Bengal
than in the Arabian Sea. Pseudeuphausia latifrons is the dominant
species in the Andaman See. Ponomareva lists Nematoscelis atlantica
as present in the Arabian Sea but does not mention it as remarkable.
Stylocheiron indicum, a new species, has so far only been recognized in
samples off western India (Silas and Mathew, 1967).
Antarctic Ocean
There are twelves species of euphausiids that have circumpolar
distributions in the Antarctic.
Off Antarctic coastlines
Euphausia crystallorophias.
Extending from Antarct'ic coast t o Antarctic Convergence (50"s60"s)
Euphausia superba; Thysanoessa mucrura.
Extending from ice edge to Antarctic Convergence
Euphausia frigida; Thysanobsa vicina.
Antarctic Convergence
Euphausia triacantha.
Antarctic Convergence to Subtropical Convergence
Euphausia vallentini, E. sirnilis, E. longirostris.
Southern regions of subtropical water
Euphausia lucens, E. similis var. armuta, E. spinifera.
The distribution of euphausiids in the Antarctic is still not absolutely
clear. Euphausia crystallorophias is a neritic species living under the
ice along the edge of the Continent. The large Euphausia superba lives
close to the ice edge and probably to a large extent under the ice, but
also extends northwards to the Antarctic Convergence, while E . frigida
occurs between the ice edge and the Antarctic Convergence. Baker
(1959) has shown that the populations of E. triacantha are intimately
associated with the Antarctic Convergence. The three species, E.
vallentini, E . similis, and E. longirostris are subantarctic species although
E . similis extends northwards to the Subtropical Convergence. The
related species, E. similis var. armata, according to Baker (1965) lives
north of the Subtropical Convergence but penetrates subantarctic
water. John (1936) classifies E . lucens as a subantarctic species but