Fig. 1

The three main sucker types of coleoid cephalopods. a–d Decabrachian type of sucker. e–g Belemnoid type of sucker. h–k Octobrachian type of sucker. a Sketch of the of the decabrachian type of sucker. b Todarodes pacificus (recent, Ommastrephidae, Oegopsida), suckers (including toothed rings) of the right tentacle. Scale bar: 5 mm. c, d Sepiola birostrata (recent, Sepiolidae, Sepiolida), isolated sucker (including smooth sucker rings) in lateral (c) and oral (d) view. Scale bar: 1 mm. e arm of Acantoteuthis speciosa (Belemnoteuthidae, Belemnitida), specimen JMS092, Blumenberg, Solnhofen Plattenkalks, Tithonian. Scale bar: 5 mm. f Close up of e showing uniserial ring-like structures. Scale bar: 5 mm. g Detailed view of a sucker of Acantoteuthis speciosa, specimen of Fuchs et. al. (2010), Eichstätt, Solnhofen Plattenkalks, Tithonian. Scale bar: 1 mm. h Sketch of the octobrachian type of sucker. i Octopus conispadiceus (Recent, Octopodidae, Incirrata). j Uniserial suckers of Mastigophora brevipinnis (Mastigophoridae, Loligosepiina), specimen MNHN 74241, La Voulte-sur-Rhone, Callovian. Scale bar: 1 mm. k Suckers of Keuppia levante (Palaeoctopodidae, Incirrata) arranged in zigzag patterns, specimen LI2011, Hâkel, Lebanon Plattenkalks, Cenomanian. Scale bar: 10 mm