200
Systematic Account
3.36 Scolecithricella dentata
Giesbrecht 1892
Scolecithrix dentata Giesbrecht, 1892: p. 266,
pI. 13 figs. 12, 20, 33, pI. 37 figs. 13, 14.
Scolecithricella dentata Sars, 1925: p. 191, pI.
52 figs. 21-23 - Rose, 1942: p. 144, figs.
38-41,46-48 - Tanaka, 1962: p. 42, fig. 130
- Owre and Foyo, 1967: p. 61, figs. 94, 379381 - Park, 1968: p. 555, pI. 18 figs. 13-16;
1980: p. 42, fig. 7 - Campaner, 1984: p. 176,
fig.6f-k.
Body length -
females: 1.84-1.96mm (10 specimens)
males: 1.76-1.94mm (4 specimens)
Female. Cephalothorax ovate, 2.5 times
longer than wide. Head rounded in dorsal
view. Rostrum with strong base and rather
short, pointed rami. A1 almost reaching
distal end of genital somite. Postero-Iateral
corners of last thoracic somite notched
on each side. Proportional lengths of
cephalothorax and abdomen 76: 24. Abdomen
4-segmented, genital somite the longest;
proportional lengths of abdominal somites
and furca 37:22:22: 8: 11 = 100. P5 1 -
jointed, fiat, with minute outer marginal
spine, one small distal spine and a relatively
large inner spine. This leg may be variable in
spinulation, with outer marginal spine absent
in some speciinens (Tanaka 1962).
Male. Cephalothorax 2.3 times longer than
wide. Postero-Iateral corners of last thoracic
somite rounded. Proportional lengths of
cephalothorax and abdomen 73: 27; proportionallengths of abdominal somites and furca
15: 30: 21: 23: 3: 8 = 100. Caudal rami about
as long as wide. In P5, right ramus with very
short endopod; both endopod and last joint
of exopod bearing short spine. In left ramus,
endopod reaching distal margin of Re1 and
bearing spine at tip; distal joint of exopod
ornated with dense bristles on inner margin.
Remarks
Most ofthe females we collected lacked a P5.
Careful examination of the specimens gave
no sign of the presence of this leg. This was
noted and remarked also by Campaner
(1984) with regards to the_ material from
epipelagic waters off Southern Brazil.
Distribution
S. dentata is a common species, widely distributed in the Mediterranean Sea (type
locality), and the Atlantic, Pacific and Indian
Oceans. Farran (1929) reported S. dentata
from the North temperate and tropical
Atlantic and off New Zealand from the
surface to 150 m. According to Campaner
(1984), it was one of the most frequent and
abundant Scolecithricella species off southern
Brazil in neritic and oceanic waters, where it
was first found by Bjornberg (1963). Park
(1980) found S. dentata in Antarctic and subAntarctic areas, north to 46°40'S, in samples
collected from the surface down to 2470 m. In
the present study, it was sampled from 200400 m at three stations in the Pacific area and
from 200-250 m at a Central station in the
Straits of Magellan.
Systematic Account
3.36 Scolecithricella dentata
Giesbrecht 1892
Scolecithrix dentata Giesbrecht, 1892: p. 266,
pI. 13 figs. 12, 20, 33, pI. 37 figs. 13, 14.
Scolecithricella dentata Sars, 1925: p. 191, pI.
52 figs. 21-23 - Rose, 1942: p. 144, figs.
38-41,46-48 - Tanaka, 1962: p. 42, fig. 130
- Owre and Foyo, 1967: p. 61, figs. 94, 379381 - Park, 1968: p. 555, pI. 18 figs. 13-16;
1980: p. 42, fig. 7 - Campaner, 1984: p. 176,
fig.6f-k.
Body length -
females: 1.84-1.96mm (10 specimens)
males: 1.76-1.94mm (4 specimens)
Female. Cephalothorax ovate, 2.5 times
longer than wide. Head rounded in dorsal
view. Rostrum with strong base and rather
short, pointed rami. A1 almost reaching
distal end of genital somite. Postero-Iateral
corners of last thoracic somite notched
on each side. Proportional lengths of
cephalothorax and abdomen 76: 24. Abdomen
4-segmented, genital somite the longest;
proportional lengths of abdominal somites
and furca 37:22:22: 8: 11 = 100. P5 1 -
jointed, fiat, with minute outer marginal
spine, one small distal spine and a relatively
large inner spine. This leg may be variable in
spinulation, with outer marginal spine absent
in some speciinens (Tanaka 1962).
Male. Cephalothorax 2.3 times longer than
wide. Postero-Iateral corners of last thoracic
somite rounded. Proportional lengths of
cephalothorax and abdomen 73: 27; proportionallengths of abdominal somites and furca
15: 30: 21: 23: 3: 8 = 100. Caudal rami about
as long as wide. In P5, right ramus with very
short endopod; both endopod and last joint
of exopod bearing short spine. In left ramus,
endopod reaching distal margin of Re1 and
bearing spine at tip; distal joint of exopod
ornated with dense bristles on inner margin.
Remarks
Most ofthe females we collected lacked a P5.
Careful examination of the specimens gave
no sign of the presence of this leg. This was
noted and remarked also by Campaner
(1984) with regards to the_ material from
epipelagic waters off Southern Brazil.
Distribution
S. dentata is a common species, widely distributed in the Mediterranean Sea (type
locality), and the Atlantic, Pacific and Indian
Oceans. Farran (1929) reported S. dentata
from the North temperate and tropical
Atlantic and off New Zealand from the
surface to 150 m. According to Campaner
(1984), it was one of the most frequent and
abundant Scolecithricella species off southern
Brazil in neritic and oceanic waters, where it
was first found by Bjornberg (1963). Park
(1980) found S. dentata in Antarctic and subAntarctic areas, north to 46°40'S, in samples
collected from the surface down to 2470 m. In
the present study, it was sampled from 200400 m at three stations in the Pacific area and
from 200-250 m at a Central station in the
Straits of Magellan.