FAO Species Identification Guide for Fishery Purposes Western

702 Cephalopods
15a. Surface of mantle, head and arms covered with many light organs (usually large and
distinct); a few small suckers at the proximal end of the manus; left eye considerably
larger than right in adults (Fig. 35) . . . . . . . . . . . . . . . . . Family Histioteuthidae (p. 787)
15b. Surface of mantle and head without light organs; many small to minute suckers (or suckers
and knobs) at proximal end of manus and along tentacle shaft; eyes equal sized (Fig. 36)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Family Architeuthidae *
light
organs
ventral view
Fig. 35 Histioteuthidae (Histioteuthis)
club
Fig. 36 Architeuthidae (Architeuthis)
16a. Funnel locking cartilage with a longitudinal and a transverse groove, ⊥-shaped or
–| -shaped . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . → 17
16b. Funnel locking cartilage oval with 1 or 2 knobs directed toward centre of concavity . . . . . . → 18
17a. Funnel locking cartilage with a longitudinal groove crossed by a transverse groove at its
posterior end, ⊥-shaped; fins less than 60% of mantle length (Fig. 37) ...........
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Family Ommastrephidae (p. 788)
17b. Funnel locking cartilage with a longitudinal groove from which a shorter groove
branches medially, –|-shaped; fin length equal to mantle length (Fig. 38) .........
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Family Thysanoteuthidae (p. 797)
funnel locking
cartilage
ventral view
Fig. 37 Ommastrephidae (Ommastrephes)
dorsal view
cluster of
suckers
knobs alternating
with suckers
tentacular
funnel locking
cartilage
dorsal view
Fig. 38 Thysanoteuthidae (Thysanoteuthis)