General Morphology

Families: Loliginidae, Sepiidae, Octopodidae

a. Mantle length
b. Fin
c. Tentacle
d. Mantle
e. Funnel
f. Arms

Family Loliginidae

This family comprises the majority of inshore or continental shelf squids. With well developed horny shell or gladius, a closed or covered eye without supplementary lids, terminal or marginal fins but always united posteriorly, and four rows of suckers on the hand portion of the tentacular club. A narrow horny skeleton called a 'pen' , which is translucent or transparent. Three genera are found in Hong Kong: Sepioteuthis, Doryteuthis and Loligo.

Family Sepiidae

Cuttlefishes range in size from several centimetres to one metre in length. All with a large dorsal chalky shell or cuttlebone internally. Each species has a slightly different skeleton. There are two genera of cuttlefish found in Hong Kong waters. Sepiella has a large pore ventrally at the posterior tip of the mantle between the fins; Sepia lacks the pore. Cuttlefish ususally inhabit in shallow waters.

Family Octopodidae

Octopuses are characterized by having no skeleton at all, and only eight arms, all of which are well-equipped with sucker discs. Without fins and possess a pair of cartilaginous stylets. The head bears a large pointed beak which can inflict a formidable bite. Two genera are presently known from Hong Kong waters: Octopus and Cistopus.