ANTdBUTIU BENTHOS
113
antarctica Koehler was recognized by Fell (1961) as being the most
abundant and widely distributed echinoderm in the Ross Sea.
East Antarctica has a fauna of 23 genera and 38 species of ophiuroids, of which 78% of the genera and 47% of the species are also found
in the Antarctic Peninsula and South Georgia. Of the 31 genera and 62
species found in the Antarctic Peninsula and South Georgia, 45% of the
genera and 25% of the species are found on the Falkland Islands and
Patagonian Shelf (Yell et al., 1969).
Some genera, e.g. Euvondrea and Glaciacantha are so far known only
from the Ross Sea. The genus Ophiosteira seems to be very well
developed in the Ross Sea, absent from the Bellingshausen Sea. Generally the Ross Sea shares at least half its species of ophiuroids with
West Antarctica.
The Antarctic ophiuroid fauna is distinguished by the stenothermal
genera, Astrohamma, Astrochlamys, Glaciacantha, Ophiosparte, Ophiodaces, Euvondrea, Ophioperla and Theodoria (Fell, 1961).
Some more eurythermal genera which appear basically Antarctic in
distribution extend to southern South America, e.g. Astrotoma,
Ophiuroglypha and Ophiurolepis. Fell (1961) considered that most
Antarctic echinoderms would not be distributed by planktonic larvae.
Viviparity and direct development are very common amongst Antarctic
echinoderms, particularly the ophiuroids. Even in those echinoderms
which possess planktonic larvae, the larval life is so short that long
distance dispersal would not be possible.
The happy conjunction of good trawl collections from the Ross Sea
together with an excellent series of photographs of the sea bottom
taken by J. S. Bullivant, in the same areas as the biological stations,
allowed Dr H. B. Fell to trace the feeding habits and some general
ecology for several ophiuroids.
The peculiar Astrotoma agassizii Lyman was traced on one photograph with the arms rolled inwards, indicating that this species probably sits on the bottom with the oral surface uppermost, using the long
arms to sweep the water and capture pelagic organisms as suggested
by Mortensen (1937).
I n some photographs Amphiura belgicae Koehler, Ophiurolepis
gelida (Koehler) and a species believed to be Ophiacantha pentactis
Mortensen could all be recognized. Amphiura belgicae was common
resting on bryozoans with the arms outspread, and may have been feeding
on the zooids of the bryozoans, or both species may have been feeding on
the plankton shower.
Ophiurolepis gelida is nearly always infected with a parasitic sponge,
Oophon radiatus Topsent, and specimens with this sponge attached
113
antarctica Koehler was recognized by Fell (1961) as being the most
abundant and widely distributed echinoderm in the Ross Sea.
East Antarctica has a fauna of 23 genera and 38 species of ophiuroids, of which 78% of the genera and 47% of the species are also found
in the Antarctic Peninsula and South Georgia. Of the 31 genera and 62
species found in the Antarctic Peninsula and South Georgia, 45% of the
genera and 25% of the species are found on the Falkland Islands and
Patagonian Shelf (Yell et al., 1969).
Some genera, e.g. Euvondrea and Glaciacantha are so far known only
from the Ross Sea. The genus Ophiosteira seems to be very well
developed in the Ross Sea, absent from the Bellingshausen Sea. Generally the Ross Sea shares at least half its species of ophiuroids with
West Antarctica.
The Antarctic ophiuroid fauna is distinguished by the stenothermal
genera, Astrohamma, Astrochlamys, Glaciacantha, Ophiosparte, Ophiodaces, Euvondrea, Ophioperla and Theodoria (Fell, 1961).
Some more eurythermal genera which appear basically Antarctic in
distribution extend to southern South America, e.g. Astrotoma,
Ophiuroglypha and Ophiurolepis. Fell (1961) considered that most
Antarctic echinoderms would not be distributed by planktonic larvae.
Viviparity and direct development are very common amongst Antarctic
echinoderms, particularly the ophiuroids. Even in those echinoderms
which possess planktonic larvae, the larval life is so short that long
distance dispersal would not be possible.
The happy conjunction of good trawl collections from the Ross Sea
together with an excellent series of photographs of the sea bottom
taken by J. S. Bullivant, in the same areas as the biological stations,
allowed Dr H. B. Fell to trace the feeding habits and some general
ecology for several ophiuroids.
The peculiar Astrotoma agassizii Lyman was traced on one photograph with the arms rolled inwards, indicating that this species probably sits on the bottom with the oral surface uppermost, using the long
arms to sweep the water and capture pelagic organisms as suggested
by Mortensen (1937).
I n some photographs Amphiura belgicae Koehler, Ophiurolepis
gelida (Koehler) and a species believed to be Ophiacantha pentactis
Mortensen could all be recognized. Amphiura belgicae was common
resting on bryozoans with the arms outspread, and may have been feeding
on the zooids of the bryozoans, or both species may have been feeding on
the plankton shower.
Ophiurolepis gelida is nearly always infected with a parasitic sponge,
Oophon radiatus Topsent, and specimens with this sponge attached