196
Systematic Account
3.35 Scaphocalanusfarrani Park 1982
Scaphocalanus farrani Park, 1982: p. 95, figs.
11-14.
Scaphocalanus brevicornis Farran, 1929: p.
248, fig. 15 - Vervoort, 1951: p. 113, figs. 60,
61; 1957, p. 107, figs. 97-99- Tanaka, 1960a:
p. 42, pI. 18 figs. 1-6 - Bradford, 1971b: p.
23, figs. 81, 82.
Body length -
females: 2.37-2.63 mm (10 specimens)
male:
2.65 mm (1 specimen)
Female. Body robust with cephalothorax 2.8
times longer than wide. Forehead broadly
rounded in dorsal view. Rostrum with two
slender filaments. Abdomen quite short; proportional lengths of cephalothorax and
abdomen 79: 21; proportional length of
abdominal somites and furca 33 : 20: 18: 12: 17
= 100. Postero-Iateral margins of last
thoracic somite somewhat triangular in
dorsal and more rounded in lateral views.
Ventral surface of genital somite with slight
protuberance and small seminal receptacle in
lateral view. First inner lobe of maxillule with
3 posterior spines. P5 2-jointed. Distal joint
with small outer spine, a medium-sized
terminal spine and a longer inner spine; these
latter are coarsely serrated along outer edge
and bear fine teeth along inner edge. P5 can
show small variations (Park 1982).
Male. Body narrowing abruptly towards the
head and ending with nearly truncated
forehead with slightly bulged mid-anterior
edge. 'Cephalothorax 2.4 times longer than
wide. Postero-Iateral margins of last thoracic
somite ending with two small rounded processes in dorsal view. Proportional lengths of
cephalothorax and abdomen 67: 33; propor-'
tionallengths of abdominal somites and furca
6: 38: 20: 23: 3: 10 = 100. Left P5 slightly
longer than exopod and ending with terminal
spine. Surface of Ril omated with small teeth
at distal end. Last exopodal joint terminating
with 2 spines and bordered with row of fine
hairs on inner margin. Right P5 asymmetrical
with short endopod ending with strong
terminal spine. Inner postero-Iateral margin
of Rei produced into large protuberance.
Exopod ending with a fine lamella with
irregular inner margin, slightly shorter than
Re2.
Remarks
According to Park (1982), the species
previously known as S. brevicornis from
Antarctic and sub-Antarctic Seas should be
considered S. farrani. S. brevicornis, as
originally described by Sars (1900) from the
Arctic Ocean, is smaller in size and differs
from S. farrani for the relative lengths and
serration of the spines of P5.
Distribution
S. farrani has been previously recorded from
the Antarctic and sub-Antarctic Seas as S.
brevicornis by Farran (1929), Vervoot (1951,
1957), Tanaka (1960a) and Bradford (1971b).
Park (1982) reports that S. farrani was one of
the most common Scaphocalanus species in
Antarctic waters. Hopkins (1985) recorded
its presence from 0-1000 m in Croker
Passage, Antarctic Peninsula. The species
has not been previously recorded in Chilean
and Argentine waters. In the present study, it
was sampled from 250-500m at three stations in the Pacific area and at one Central
station in the Straits of Magellan.
Systematic Account
3.35 Scaphocalanusfarrani Park 1982
Scaphocalanus farrani Park, 1982: p. 95, figs.
11-14.
Scaphocalanus brevicornis Farran, 1929: p.
248, fig. 15 - Vervoort, 1951: p. 113, figs. 60,
61; 1957, p. 107, figs. 97-99- Tanaka, 1960a:
p. 42, pI. 18 figs. 1-6 - Bradford, 1971b: p.
23, figs. 81, 82.
Body length -
females: 2.37-2.63 mm (10 specimens)
male:
2.65 mm (1 specimen)
Female. Body robust with cephalothorax 2.8
times longer than wide. Forehead broadly
rounded in dorsal view. Rostrum with two
slender filaments. Abdomen quite short; proportional lengths of cephalothorax and
abdomen 79: 21; proportional length of
abdominal somites and furca 33 : 20: 18: 12: 17
= 100. Postero-Iateral margins of last
thoracic somite somewhat triangular in
dorsal and more rounded in lateral views.
Ventral surface of genital somite with slight
protuberance and small seminal receptacle in
lateral view. First inner lobe of maxillule with
3 posterior spines. P5 2-jointed. Distal joint
with small outer spine, a medium-sized
terminal spine and a longer inner spine; these
latter are coarsely serrated along outer edge
and bear fine teeth along inner edge. P5 can
show small variations (Park 1982).
Male. Body narrowing abruptly towards the
head and ending with nearly truncated
forehead with slightly bulged mid-anterior
edge. 'Cephalothorax 2.4 times longer than
wide. Postero-Iateral margins of last thoracic
somite ending with two small rounded processes in dorsal view. Proportional lengths of
cephalothorax and abdomen 67: 33; propor-'
tionallengths of abdominal somites and furca
6: 38: 20: 23: 3: 10 = 100. Left P5 slightly
longer than exopod and ending with terminal
spine. Surface of Ril omated with small teeth
at distal end. Last exopodal joint terminating
with 2 spines and bordered with row of fine
hairs on inner margin. Right P5 asymmetrical
with short endopod ending with strong
terminal spine. Inner postero-Iateral margin
of Rei produced into large protuberance.
Exopod ending with a fine lamella with
irregular inner margin, slightly shorter than
Re2.
Remarks
According to Park (1982), the species
previously known as S. brevicornis from
Antarctic and sub-Antarctic Seas should be
considered S. farrani. S. brevicornis, as
originally described by Sars (1900) from the
Arctic Ocean, is smaller in size and differs
from S. farrani for the relative lengths and
serration of the spines of P5.
Distribution
S. farrani has been previously recorded from
the Antarctic and sub-Antarctic Seas as S.
brevicornis by Farran (1929), Vervoot (1951,
1957), Tanaka (1960a) and Bradford (1971b).
Park (1982) reports that S. farrani was one of
the most common Scaphocalanus species in
Antarctic waters. Hopkins (1985) recorded
its presence from 0-1000 m in Croker
Passage, Antarctic Peninsula. The species
has not been previously recorded in Chilean
and Argentine waters. In the present study, it
was sampled from 250-500m at three stations in the Pacific area and at one Central
station in the Straits of Magellan.