Schneider, 1784
Highly specialised marine molluscs; divided into two distinctive subclasses, the shelled subclass Nautiloidea and the subclass Coleoidea, in which the shell is reduced and internal or lacking entirely. About 600 species worldwide, typically nektonic or bentho-pelagic, fast moving, predatory. Foot modified to form grasping arms, intimately associated with the head, which has greatly developed eyes, a marked development of the cerebral ganglia, and a powerful beak.
[Hayward and Ryland, 1990]
The key to 38 pelagic cephalopod species of the North Sea starts at Page 395: Cephalopoda; both adult and "larvae" (juveniles) can be identified. The following species are included:
Class Cephalopda
Subclass Coleoidea
Order Sepioidea
Family Sepiidae
Sepia elegans
Sepia officinalis
Sepia orbignyana
Sepiella japonica
Family Sepiolidae
Rossia macrosoma
Rossia palpebrosa
Sepietta neglecta
Sepietta oweniana
Sepiola atlantica
Sepiola aurantiaca
Order Teuthoidea
Suborder Myopsida
Family Loliginidae
Alloteuthis medius
Alloteuthis subulatus
Loligo forbesii
Loligo vulgaris
Suborder Oegopsida
Family Brachioteuthidae
Brachioteuthis riisei
Family Cranchiidae
Galiteuthis armata
Teuthowenia megalops
Family Gonatidae
Gonatus steenstrupi
Gonatus fabricii
Family Ommastrephidae
Ommastrephes bartramii
Stenoteuthis pteropus
Illex coindetti
Todaropsis eblanae
Todarodes sagittatus
Family Onychoteuthidae
Onychoteuthis banksii
Family Architeuthidae
Architeuthis dux
Order Octopoda
Suborder Cirrata
Family Cirroteuthidae
Cirroteuthis muelleri
Suborder Incirrata
Family Octopodidae
Eledone cirrhosa
Octopus vulgaris
Family Alloposidae
Haliphron atlanticus