FAO Species Identification Guide for Fishery Purposes Western

790 Cephalopods
4a. Mantle very slender, with elongated posterior tail
(Fig. 4) . . . . . . . . . . . . . . . . . . . .Ornithoteuthis volatilis
4b. Mantle moderately stout, without an elongated tail
(Fig. 5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . → 5
5a. Large medial tentacular sucker rings with a large tooth
in each quadrant, separated by smaller subequal teeth
(Fig. 5a) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . → 6
5b. Large medial tentacular sucker rings with equal-sized
or subequal teeth or with a single larger tooth present
distally (Fig. 5b, c) . . . . . . . . . . . . . . . . . . . . . . . . → 7
6a. Two small round light organs on the intestine, one
anteriorly near the anus and the other posteriorly
(Fig. 6); ventral mantle uniformly coloured . . . . . . .
. . . . . . . . . . . . . . . . . . . . . Sthenoteuthis oualaniensis 2/
(form without a dorsal light-organ patch)
6b. No light organs on the intestine, but small spherical
sub-cutaneous light organs distributed broadly in the
ventral mantle in larger specimens (visible in the mantle
wall when cut midventrally); mantle with a midventral
bronze stripe (Fig. 7) . . . . . . . . . . . . Ommastrephesbartramii
7a. Medial tentacular sucker rings
with approximately 30 subequal
teeth (Figs 8a and 9) . . Todaropsis eblanae
7b. Medial tentacular sucker rings
with less than 25 teeth
(Fig. 8a, c) . . . . . . . . . . . . . . . . → 8
8a. Medial tentacular sucker rings
with a single larger tooth distally
(Fig. 8c) . . . . . . . . . . . . . . . . . → 9
8b. Medial tentacular sucker rings
with 16 to 20 subequal teeth
(Figs 8b and 10) ........
. . . . . . . .Todarodes pacificus subspecies
intestine
funnel
mantle
internal view of anterior
ventral mantle
2 light
organs
Fig. 6 Sthenoteuthis oualaniensis
2/ See footnote on previous page.
a) with large tooth
in each quadrant
ventral view
bronze
stripe
Fig. 7 Ommastrephes bartramii
about 30
teeth
16-20
subequal
teeth
ventral view
tail
enlongated,
pointed
Fig. 4 Ornithoteuthis volatilis
b) with subequal
teeth
large tooth
Fig. 5 tentacular sucker rings
c) with single large
tooth distally
a) Todaropsis eblanae
b) Todarodes pacificus
large tooth
distally
c) Nototodarus hawaiiensis
Fig. 8 medial tentacular
sucker rings