
Elongated, oval or arrow shaped, with easily recognisable body- and head-part; head with 8 or 10 arms with suckers
Step 3

Head and body not clearly differentiated; head usually with 4 tentacles (may be 6, 2 or absent); body may have all kinds of protruding elements, but never sucker-bearing arms
Step 23

Worm-shaped; no arms or other protruding elements; body covered with calcified scales or spicula
Step 110
128 possible taxa remaining show common names
- Acanthodoris pilosa
- Adalaria proxima
- Aegires punctilucens
- Aeolidia papillosa
- Aeolidiella glauca
- Alderia modesta
- Aldisa zetlandica
- Alloteuthis media
- Alloteuthis subulata
- Ancula gibbosa
- Aplysia punctata
- Archidoris pseudoargus
- Armina loveni
- Asperspina brambelli
- Berthella plumula
- Brachioteuthis riisei
- Cadlina laevis
- Calliopaea bellula
- Chaetoderma nitidulum
- Colpodaspis pusillus
- Corambe obscura
- Coryphella browni
- Coryphella gracilis
- Coryphella lineata
- Coryphella pedata
- Coryphella pellucida
- Coryphella verrucosa
- Cuthona amoena
- Cuthona caerulea
- Cuthona concinna
- Cuthona foliata
- Cuthona gymnota
- Cuthona nana
- Cuthona pustulata
- Cuthona rubescens
- Cuthona viridis
- Dendronotus frondosus
- Doto coronata
- Doto cuspidata
- Doto dunnei
- Doto fragilis
- Doto millbayana
- Doto pinnatifida
- Doto tuberculata
- Eledone cirrhosa
- Elysia viridis
- Embletonia pulchra
- Eubranchus cingulatus
- Eubranchus doriae
- Eubranchus exiguus
- Eubranchus farrani
- Eubranchus pallidus
- Eubranchus tricolor
- Eubranchus vittatus
- Facelina bostoniensis
- Facelina coronata
- Falcidens crossotus
- Favorinus blianus
- Favorinus branchialis
- Galiteuthis armata
- Geitodoris planata
- Gonatus fabricii
- Goniodoris castanea
- Goniodoris nodosa
- Hermaea bifida
- Hero formosa
- Illex coindetii
- Janolus cristatus
- Janolus hyalinus
- Jorunna tomentosa
- Limacia clavigera
- Limapontia capitata
- Limapontia depressa
- Limapontia senestra
- Loligo forbesi
- Loligo vulgaris
- Lomanotus genei
- Lomanotus marmoratus
- Microhedyle lactea
- Nematomenia banyulensis
- Neomenia carinata
- Octopus vulgaris
- Okenia leachii
- Okenia quadricornis
- Ommastrephes bartramii
- Onchidoris depressa
- Onchidoris fusca
- Onchidoris inconspicua
- Onchidoris luteocincta
- Onchidoris muricata
- Onchidoris pusilla
- Onchidoris sparsa
- Philine angulata
- Philine aperta
- Philine catena
- Philine pruinosa
- Philine punctata
- Philine quadrata
- Philine scabra
- Philinoglossa helgolandica
- Placida dendritica
- Pleurobranchus membranaceus
- Polycera dubia
- Polycera faeroensis
- Polycera notha
- Polycera quadrilineata
- Rhopalomenia aglaopheniae
- Rossia macrosoma
- Rossia palpebrosa
- Rostanga rubra
- Runcina coronata
- Scutopus ventrolineatus
- Sepia elegans
- Sepia officinalis
- Sepiella japonica
- Sepietta neglecta
- Sepietta oweniana
- Sepiola atlantica
- Sepiola aurantiaca
- Tenellia adspersa
- Tergipes tergipes
- Teuthowenia megalops
- Thecacera pennigera
- Todarodes sagittatus
- Todaropsis eblanae
- Tritonia hombergi
- Tritonia lineata
- Tritonia plebeia
Decision path