Notes
Records: 706(+ 83 records of .aff
This species has repeatedly been
confused with both C. hyalophyllum and C. parvidentata. Moreover,
specimens from both the North and South Pacific formerly attributed to this
species are not the same, but are yet to be formally described. Records from
the North Pacific have neither been included in the count given above, nor have
their distributions been included in the maps. Müller (1906) described a
subspecies from the Indian Ocean, C. magna
rhombica, which was differentiated from the type species by having an
acutely angled posterior dorsal corner; this subspecies has not been reported
since. So in the context of this confusion and uncertainty it is unfortunate
that C. magna was designated as the type species for the genus Conchoecia
by Sylvester-Bradley & Iles (1956), who at the same time regularized
the use of the current spelling (Dana’s original spelling was Conchaecia).
Angel (1969) redescribed the species when clearing up the confusion between it
and C. hyalophyllum and Porroecia parthenoda. However, the exact
status of Skogsberg’s (1930) species Conchoecia tetragona remains
unresolved. The geographical range of C. magna is from 54°S to
54°N. Females are most abundant at daytime depths of 100-500m but also
occur regularly to depths of 1000m, whereas males and juveniles are most
abundant at 100-300m. The bathymetric profiles show that the species is
predominantly shallow mesopelagic and undertakes diel vertical migrations. At
night a large proportion of adults migrate to depths of 25-50m and juveniles
move even shallower and are even caught in small numbers in the neuston at
night (Angel (1979).
Living
specimens are translucent with orange and red pigmentation associated with the
bases of the limbs.
N. Atlantic
|
n
|
Mean mm
|
s.d
|
Range mm
|
Female
|
217
|
1.99
|
0.080
|
1.80-2.18
|
Male
|
165
|
1.93
|
0.054
|
1.84-2.08
|
A-1
|
23
|
1.22
|
0.093
|
1.08-1.38
|
A-2
|
11
|
0.79
|
0.029
|
0.74-0.84
|
A-3
|
14
|
0.58
|
0.043
|
0.52-0.70
|