Comparative Morphology of Modern and Fossil Coleoid Jaw Apparatuses

N. Jb. Geol. Paläont. Abh. 266/1, 9–18 Article Stuttgart, October 2012

Comparative morphology of modern and fossil coleoid jaw apparatuses

Kazushige Tanabe With 5 figures

Tanabe, K. (2012): Comparative morphology of modern and fossil coleoid jaw apparatuses. – N. Jb. Geol. Paläont. Abh., 266: 9–18; Stuttgart.

Abstract: Current knowledge about the jaw apparatuses (i.e. beaks or mandibles) of modern and fossil cephalopods is reviewed with special reference to those of coleoids. In modern cephalopods, the jaw apparatus is housed in the buccal mass and consists of articulated upper and lower jaws, which have a special function to bite and cut up a prey with the aid of the surrounding jaw muscles. Both the upper and lower jaws are composed mainly of a darkly tinted chitin-protein complex. The jaw apparatuses of extant coleoids are characterised by a posteroventrally elongated inner lamella in the lower jaw and the absence of a calcareous jaw element. These features are clearly distinguishable from those of nautilid jaws, which possess a substantially reduced inner lamella of the lower jaw and calcareous tips in both the upper and lower jaws. Recent discoveries of well-preserved jaws referable to vampyropod and possibly teuthid coleoids from the Late Cretaceous of the North Pacific fill the gap in the relatively poor fossil record of the Coleoidea; they clearly demonstrate that large non- belemnoid coleoids existed in this bioprovince together with ammonoids and nautilids.

Key words: Cephalopoda, Coleoidea, jaw apparatus, comparative morphology.

1. Introduction Lowenstam et al. 1984; Gupta et al. 2008) with anterior calcareous tips in both the upper and lower jaws One of the diagnostic features shared by all modern for Nautilus and Allonautilus (Nautilida) (Okutani & cephalopods is the development of a well-developed Mikami 1977; Saunders et al. 1978). jaw apparatus (i.e. beaks or mandibles). The jaw appa- The chitinous jaw portions of cephalopods have ratus is accommodated within the globular muscular preservation potential as fossils when replaced by organ called the buccal mass in the proximal portion phosphoric minerals or pyrite during diagenesis (Tan- of the digestive tract. Because of its essential role in abe & Fukuda 1983; Landman et al. 2006; Tanabe et predacious-scavenging modes of feeding and wide tax- al. 2008, 2012). In fact, fossilised chitinous and cal- onomic distribution in modern taxa, there is no doubt careous jaw remains of cephalopods are known to oc- that all extinct cephalopods also had a jaw apparatus. cur in Late Palaeozoic and younger marine deposits The jaw apparatus of extant cephalopods consists of (Tanabe & Fukuda 1999). Most are found individu- upper and lower elements that are composed mainly of ally, although they are rarely preserved in situ within an organic hard substance comprising chitin–protein the body chambers of ammonoids (e.g. Lehmann 1976, complex (Saunders et al. 1978; Hunt & Nixon 1981; 1980, 1990; Doguzhaeva & Mutvei 1992; Tanabe &

Landman 2002; Kruta et al. 2011; Tanabe et al. 2012; Dilly & Nixon (1976) situated between them (Tanabe Klug & Jerjen 2012) and nautilids (e.g. Klug 2001) & Fukuda 1987; Fig. 1B-C). The outer lamellae of the and/or within the mouthpart portion of exceptionally upper and lower jaws are mostly covered by a thin buc- well-preserved coleoids with soft-tissue remains from cal membrane and are free of muscle. Konservat Lagerstätten (e.g. Klug et al. 2005, 2010a, In Nautilus, the distal ends of beccublasts are deep- b; Fuchs & Larson 2011). ly inserted within the hard chitinous plate, forming Morphological analysis of isolated jaw fossils from numerous micropores on it (Fig. 1E). In coleoids, the Late Cretaceous marine deposits in Hokkaido (Japan) attachment scars of beccublasts on the jaw plates lack and Vancouver Island (Canada) compared with mod- micropores and instead consist of anchor-type aligned ern and fossil cephalopod jaws whose taxonomic rela- polygonal imprints (Dilly & Nixon 1976) (Fig. 1D). tionships are known shows that diverse non-belemnoid Therefore, the branching ends of the beccublasts may coleoid fauna existed in the Late Cretaceous North serve to firmly attach the jaw muscles onto the jaw Pacific (Tanabe et al. 2006, 2008; Tanabe & Hikida plates, especially in Nautilus. The outer surface of the 2010). This article synthesises the current knowl- buccal mass is wholly covered by a thin layer of con- edge on modern and fossil coleoid jaws and discusses nective tissue, except for the oral opening. The labial their evolutionary implications. margin (‘lips’) encircles the oral opening and consists of several rows of dense, triangular projections that Institutional abbreviations: CDM, Courtenay and Dis- include tall columnar epithelial, mucus-secreting, and trict Museum and Palaeontology Centre, British Columbia, sensory cells; the tall columnar epithelial cells secrete Canada. UMUT, University Museum of the University of Tokyo, Japan. NMA, Nakagawa Museum of Natural His- an anterior calcareous covering on the jaw plates in tory, Hokkaido, Japan. KMNH, Kitakyushu Museum of Nautilus (Fukuda 1980; Tanabe & Fukuda 1987). The Natural History and Human History, Kitakyushu, Japan. sharply pointed rostral tips of the upper and lower jaws NSM, National Museum of Nature and Science, Tokyo, Ja- of extant cephalopods appear to serve for biting and pan. AMNH, American Museum of Natural History, New cutting up prey by means of strong jaw muscles. York, USA. The radula of cephalopods is composed of a series of tooth rows. In Nautilus, each transverse row consists of a total of 9 teeth with 2 pairs of marginal sup- 2. Cephalopod buccal mass structure port plates; meanwhile, in most coleoids, each row is composed of 7 teeth, with a pair of marginal plates In extant cephalopods, the upper and lower jaws are (Nixon 1995). The pelagic coleoid Spirula lacks a rad- housed in the globular-shaped proximal portion of the ula (Kerr 1931). digestive tract called the buccal mass (Tanabe & Fuku- The radular teeth are secreted by a thick epithelium da 1999) (Fig. 1A-B). The buccal mass has well-devel- consisting of columnar cells (odontoblasts) that line oped muscular systems that support active movement the posterior portion of the radular sac (Raven 1958) of the jaws and radula. Inside the buccal cavity is the (Fig. 1A). The radulae of extant cephalopods are much radular complex, which is composed of the radula, sali- smaller than their jaws. In coleoids, the radular mus- vary glands, salivary papilla, and 2 lateral buccal palps cles stiffen and elongate during the forward movement (Fig. 1A). The inner side of the lower jaw and outer side of the radula; this action is supplemented by power- of the upper jaw are connected by jaw muscles with a ful retractor muscles (Young 1993). In Nautilus, the thin layer of tall columnar cells named beccublasts by radular muscles are rigidly attached anteriorly to the

Fig. 1. Cephalopod buccal mass structure. A – Diagram of a buccal mass structure of modern Nautilus (median section). Modified fromT anabe & Fukuda (1987, fig. 1).B – Photomicrograph of a cross-sectioned buccal mass of a cuttlefish,Sepia esculenta, captured in the Sea of Japan, west Japan. Stained with haematoxylin-eosin solution. C – Close-up photo of the portion shown in B, showing beccublasts between upper jaw plate and jaw muscle. D, E – SEM’s of the attachment scar of beccublasts on the jaw surface. D – Sepia esculenta. Anchor-type attachment scar of beccublasts on the outer surface of the upper jaw. UMUT RM 31010 from the Sea of Japan, west Japan. E – Nautilus pompilius. Outer surface of the upper jaw, showing micropores into which the branching ends of the becculasts are deeply inserted. UMUT RM 31011 from off Suva, Fiji. Photographs by courtesy of Y. Fukuda for B and C. Comparative morphology of modern and fossil coleoid jaw apparatuses 11

Fig. 1. 12 K. Tanabe lip of the radular sac and retractors are less developed. These conditions appear to allow subtle movement of the radula for scraping and conveying small chewed pieces of food towards the oesophagus (Altmann & Nixon 1970; Fukuda 1980).

3. Comparative morphology and structure of extant coleoid jaw apparatuses The gross morphology and descriptive terms of a modern coleoid jaw apparatus are diagrammed in Fig. 2. Comparative morphological studies of modern and fossil cephalopod jaws show that the jaw apparatuses of modern coleoids are distinguishable from those of nautilids and ammonoids by having a substantially posteriorly elongated inner lamella (crest and lateral wall in Fig. 2) in the lower jaw and absence of a calcar- Fig. 2. Diagram of the jaw apparatus of an extant sepiid, eous element that occurs in the jaws of nautilids and Sepia officinalis (left lateral view). Both upper and lower some ammonoids (Clarke 1986; Tanabe & Fukuda jaws consist of outer (hood and wing) and inner (crest and 1999). Furthermore, detailed morphological analyses lateral wall) lamellae. Terms are according to Clarke (1962, of key characters facilitate the suprageneric-level clas- 1986) and Clarke & Maddock (1988). sification of coleoid jaws C( larke 1962, 1986; Clarke & Maddock 1988; Kubodera 2000; Neige & Dommer- gues 2002) even if they are preserved individually in stomachs, regurgitations, and excrements of predators 3.9) are both characterized by a more widely open such as whales, seals, sharks, and birds (Clarke 1986). wing on the outer lamella and shorter crest and lat- The lower jaws of the Teuthida are characterised eral wall on the inner lamella than those of other cole- by the posteroventrally expanded lateral wall (= in- oids. The anterior tip in the lower jaw of V. infernalis ner lamella in other terminologies) and the presence is more sharply pointed than that of the cirroctopods. of a strong lateral fold (Clarke 1962, 1986; Clarke & Maddock 1988; Fig. 3.1-3.3). Those of the Sepiida have a relatively short rostrum and a parallelogram- 4. Jaws of Late Cretaceous non-belemnoid shaped lateral wall (Fig. 3.4-3.5). By contrast, the coleoids from the North Pacific lower jaws of the Octopoda are distinguishable from those of other coleoids by a substantially posteriorly Recently, well-preserved upper and lower jaw fossils elongated lateral wall with a distinct median radial referable to the Coleoidea were discovered from the fold (Fig. 3.6-3.7). Upper Cretaceous marine deposits in the North Pacific The lower jaws of the cirroctopods (Fig. 3.8) and regions (i.e. Hokkaido and Vancouver Island) (Tanabe the vampyromorph Vampryoteuthis infernalis (Fig. et al. 2006, 2008; Tanabe & Hikida 2010) (Fig. 4).

Fig. 3. Comparison of the lower jaws in selected extant coleoids. Frontal (a) and lateral (b) views for each figure. As perK u- bodera (2000) for 8 and 9. Each scale bar represents 10 mm. 1a, b – Dosidicus gigas (Ommastrephidae, Teuthida). UMUT 31004 from 122 m depth off Baja California, Mexico. 2a, b – Architeuthis kirki (Architeuthidae, Teuthida). AMNH291938 from 671-674 m depth, Merneo Bank, Chatham Rise, New Zealand. 3a, b – Todarodes pacificus (Ommastrephidae, Teuth- ida). UMUT 31005 from the Sea of Japan, central Japan. 4a, b – Sepia officinalis (Sepiidae, Sepiida). Unregistered AMNH specimen from the Northeast Atlantic. 5a, b – Sepia latimanus (Sepiidae, Sepiida). UMUT RM 31006 from off Ishigaki Island, southern Japan. 6a, b – Octopus vulgaris (Octopodidae, Octopoda). UMUT 31007 from the Mediterranean Sea (detailed locality unknown). 7a, b – Octopus membranaceus (Octopodidae, Octopoda). UMUT 31008 from the water off Thailand (detailed locality unknown). 8a, b – Cirrothauma sp. (Cirroteuthidae, Cirroctopoda). Unregistered NSM specimen found in a shark’s stomach, Northwest Pacific. 9a, b – Vampyroteuthis infernalis (Vampyroteuthidae, Vampyromor- pha). Unregistered NSM specimen. Detailed locality unknown. Comparative morphology of modern and fossil coleoid jaw apparatuses 13

Fig. 3. 14 K. Tanabe

Fig. 4. Lower jaws attributed to Vampyromorpha (1-4) and Cirroctopoda (5-7) from the Upper Cretaceous of Hokkaido, Japan, and Vancouver Island, Canada. Frontal (a) and lateral (b) views are shown for each specimen. Abbreviations: ol: outer lamella, il: inner lamella. Each scale bar represents 10 mm. 1a, b – Nanaimoteuthis jeletzkyi Tanabe. CDM 2006.1.1. From the lower Campanian, northwest of Courtenay, Vancouver Island. 2a, b – Nanaimoteuthis jeletzkyi Tanabe. UMUT MM 31009. From the lower Campanian in Haboro area, northwest Hokkaido. 3a, b – Nanaiomteuthis sp. nov. KMNH IvP 202001. From the lower Campanian in Haboro area, northwest Hokkaido. 4a, b – Nanaimoteuthis yokotai Tanabe & Hik- ida. UMUT MM 30337. From the middle Turonian in Obira area, northwest Hokkaido. 5a, b – Paleocirroteuthis pacifica Tanabe. CDM 2006.2.1. From the lower Campanian, northwest of Courtenay, Vancouver Island. 6a, b – Paleocirroteuthis pacifica Tanabe. NMA 284. From the lower Campanian in Nakagawa area, northern Hokkadio. 7a, b – Paleocirroteuthis haggarti Tanabe. CDM 994.59.9. From the Santonian, near Courtenay, Vancouver Island. Comparative morphology of modern and fossil coleoid jaw apparatuses 15

Fig. 5. Phylogenetic scheme of the Vampyropoda proposed by Fuchs (2006) and Fuchs & Weis (2010). New fossil records of vampryomorph and cirroctopod jaws from the North Pacific are given in black circles.

They occurred individually in calcareous concretions Hokkaido (Fig. 4.4a, b); and (3) Paleocirroteuthis hag- and retain their original three-dimensional structure. garti and P. pacifica of the order Cirroctopoda from These jaws are composed wholly of black carbonate the Santonian of Vancouver Island (Fig. 4.7a, b) and apatite (Tanabe et al. 2008), which might be diageneti- the Campanian of Hokkaido and Vancouver Island cally replaced chitin-protein complex. (Fig. 4.5a, b-4.6a, b), respectively. The lower jaws consist of a posteriorly elongated The upper jaw of Y. giganteus is extremely large, inner lamella and a widely open outer lamella with a measuring 97 mm in maximum length; it is compa- pointed rostrum, while the upper jaws are composed rable in size to the upper jaws of modern giant squids of posteriorly elongated large inner and short outer la- (Architeuthis spp.) whose total body length exceeds 5 mellae with a sharply pointed rostrum. In all of these m (Tanabe et al. 2006). Similarly, the lower jaws of lower jaws, the crest and lateral wall of the inner lamel- Nanaimoteuthis and Paleocirroteuthis species are la are elongated less posteroventrally and are covered large (38-110 mm maximum length of the outer lamel- mostly by the hood and wing of the outer lamella (Fig. la) compared with those of modern vampyromorphid 4). In modern coleoids, these features of the lower jaws and cirroctopodid species. In all modern coleoids, the are only observed in the orders Cirroctopoda and the jaw size is allometrically strongly negative in relation Vampyromorpha of the superorder Vampyropoda (v. to the total body weight and mantle length (Clarke Boletzky 1992). Comparison with the jaws of modern 1962, 1986). These lines of evidence suggest that the coleoids allows us to recognise the following 3 gen- Cretaceous coleoids described by Tanabe et al. (2006, era and 5 species in the available material examined: 2008) and Tanabe & Hikida (2010) all had much larger (1) an upper jaw of Yezoteuthis giganteus of the order body sizes than their modern representatives. Teuthida from the Campanian of Hokkaido (Tanabe et Fossil records of coleoid shell remains are impor- al. 2006); (2) lower jaws of Nanaimoteuthis of the or- tant if we consider the possible sources of the isolated der Vampryomorpha, N. jeletzkyi from the Campanian coleoid jaws examined. In the North Pacific region, of Vancouver Island (Fig. 4.1a, b) and Hokkaido (Fig. belemnite phragmocones and rostra have not yet been 4.2a, b), N. sp. nov. from the Campanian of Hokkaido found from post-Albian Cretaceous deposits (Iba et (Fig. 4.3a, b), and N. yokotai from the Turonian of al. 2011). Instead, shell remains (e.g. phragmocones 16 K. Tanabe and gladii) of the following non-belemnitid coeloids on the jaw and shell remains support the view that are reported from the Upper Cretaceous of the region: modern-type coleoid clades such as Spirulida, Cirroc- (1) Cyrtobelus and a new genus of the order Spirulida topoda, and Vampyromorpha presumably have their from the Campanian of Vancouver Island (Fuchs et origins in the North Pacific and already appeared at al. 2012) and the Upper Cretaceous of Hokkaido and least by the Late Cretaceous (Turonian) time before southern Alaska (formerly identified as Naefia and re- the Cretaceous/Palaeogene boundary mass extinction named by Fuchs et al. in prep.) respectively; (2) Cono- event (Iba et al. 2011). teuthis of the order Diplobelida from Hokkaido (Fuchs & Niko 2010; Fuchs et al. 2011); and (3) Actinosepia Acknowledgements of the suborder Teudopseina from Vancouver Island (Fuchs et al. 2007). Conoteuthis, Cyrtobelus, and the This paper is a summary of my talk given at the 4th Inter- new spirulid genus are all represented by small phrag- national Symposium ‘Coleoid Cephalopods Through Time’ mocones, usually less than 10 cm long, although the (Stuttgart, September 6-9, 2011). I express my gratitude to the organisers Günter Schweigert (Stuttgart), Dirk Fuchs proostracum length in these genera is still unknown. (Berlin), and Gerd Dietl (Stuttgart) for giving me the op- In view of their small phragmocones, these genera portunity to give a talk at the symposium; Neil H. Land- may be excluded as a source for the coleoid jaws ex- man (New York) for facilitating observation of jaws of the amined. giant squid (Architeuthis kirki) and Sepia officinalis in his Among the known Late Cretaceous coleoids from care; and Royal H. Mapes (Athens, Ohio), Yoshio Fukuda (Chiba) and Akihiro Misaki (Kitakyushu) for kindly pro- the North Pacific region, Actinosepia from Vancouver viding alcohol-fixed buccal masses of a Humboldt squid Island is represented by relatively large gladii, approx- (Dosidicus gigas), photomicrographs of a thin-sectioned imately 30 cm in maximum length. This genus can be Sepia esculenta buccal mass, and an interesting Cretaceous considered as a source of one of the examined lower vampyropod jaw specimen respectively for this study. Spe- jaws from Vancouver Island, that was identified as be- cial thanks are due to Dirk Fuchs and Christian Klug for critical comments to improve this manuscript. longing to the Octopoda by Tanabe et al. (2008, fig. 9); however, this hypothesis requires further support by fossils showing a gladius-jaws association. References The suborders Teudopseina (Starobogatov 1983) Altman, J.S. & Nixon, M. (1970): Use of the beaks and rad- including Actinosepia and Prototeuthina (Naef 1921) ula by Octopus vulgaris in feeding. – Journal of Zoo- are extinct gladius-bearing taxa that ranged from the logical Society of London, 161: 25-38. Late Triassic to the end of the Cretaceous (Fuchs 2006) Boletzky, S. v. (1992): Evolutionary aspects of develop- (Fig. 5). The jaw apparatuses of the Prototeuthina are ment, life style, and reproduction mode in incirrate poorly known, but those of the Teudopseina preserved octopods (Mollusca, Cephalopoda). – Revue Suisse de Zoologie, 4: 755-770. in soft-tissue remains and/or in association with gladii Clarke, M.R. (1962): The identification of cephalopod are known from genera such as Trachyteuthis, Ple- “beaks” and the relationship between beak size and total sioteuthis, and Leptotheuthis from the Late Jurassic body weight. – Bulletin of the British Museum (Natural in southern Germany (Klug et al. 2005, 2010a) and History), Zoology, 8: 419-480. Glyphiteuthis from the Cenomanian in Lebanon Clarke, M.R. (1986): A Handbook for the Identification of Cephalopod Beaks. – 273 pp.; Oxford (Clarendon Press). uchs arson (F & L 2011). The jaws of these genera dif- Clarke, M.R. & Maddock, L. (1988): Beaks of living cole- fer from the Cretaceous coleoid jaws from the North oid Cephalopoda. – In: Clarke, M.R. & Trueman, E.R. Pacific due to their much smaller size and the more (Eds.): The Mollusca. Vol. 12. Paleontology and Neon- posteriorly projected inner lamella for the lower jaws. tology of Cephalopods, 121-131; San Diego (Academic In summary, our knowledge of fossil coleoid jaws Press). Dilly, P.N. & Nixon, M. (1976): The cells that secrete the is still insufficient. However, the discovery of well-pre- beaks in octopods and squids (Mollusca, Cephalopoda). served jaws of octobrachiates and teuthids by Tanabe – Cell and Tissue Research, 167: 229-241. et al. (2006, 2008) and Tanabe & Hikida (2010) from Doguzhaeva, L.A. & Mutvei, H. (1992): Radula of the Ear- the Upper Cretaceous of the circum-North Pacific re- ly Cretaceous ammonite Aconeceras (Mollusca: Cepha- gions help to fill some of the gaps in the fossil record lopoda). – Palaeontographica, (A), 223: 167-177. Fuchs, D. (2006): Fossil erhaltungsfähige Merkmalskom- of the Coleoidea (Fig. 5), which might be originated plexe der Coleoidea (Cephalopoda) und ihre phylo- within the order Bactritida, a group of extinct cepha- genetische Bedeutung. – Berliner Paläobiologische Ab- lopods with straight, external shells in the Early Car- handlungen, 8: 1-115. boniferous (Kröger et al. 2011). Available fossil data Fuchs, D., Beard, G., Tanabe, K. & Ross, R. (2007): Cole- Comparative morphology of modern and fossil coleoid jaw apparatuses 17

oid cephalopods from the Late Cretaceous Northeastern Klug, C., Schweigert, G., Fuchs, D. & Dietl, G. (2010b): Pacific. In: Seventh International Symposium Cepha- First record of a belemnite preserved with beaks, lopods – Present and Past, 2007, Sapporo, Japan, Ab- arms and ink sac from the Nusplingen Lithographic stracts Volume, 131; Sapporo. Limestone (Kimmeridgian, SW Germany). – Lethaia, Fuchs, D., Keupp, H., Trask, P. & Tanabe, K. (2012): Tax- 43: 445-456. Published online October 2010; DOI: onomy, morphology and phylogeny of Late Cretacerous 10.1111/j.1502-3931.2009.00203.x. spirulid coleoids (Cephalopoda) from Greenland and Kröger, B., Vinther, J. & Fuchs, D. (2011): Cephalopod Canada. – Palaeontology, 55: 285-303. origin and evolution: A congruent picture emerging Fuchs, D., Keupp, H. & Wiese, F. (2011): Protoconch mor- from fossils, development and molecules. – Bioessays, phology of Conoteuthis (Diplobelida, Coleoidea) and 33: 602-613. its implications on the presumed origin of the Sepiida. Kruta, I., Landman, N.H., Rouget, I., Cecca, F. & Taffor- – Cretaceous Research, 34: 200-207. Published online eau, P. (2011): The role of ammonites in the Mesozoic November 2011; DOI:10.1016/j.cretres.2011.10.018. marine food web revealed by jaw preservation. – Sci- Fuchs, D. & Larson, N.L. (2011): Diversity, morphology, ence, 331: 70-72. and phylogeny of coleoid cephalopods from the Upper Kubodera, T. (2000): Identification of jaws in modern cole- Cretaceous plattenkalks of Lebanon – Part II: Teudop- oid cephalopods. http://research.kahaku.go.jp/zoology/ seina. – Journal of Paleontology, 85: 815-834. Beak/ Fuchs, D. & Niko, S. (2010): The first diplobelid belemnoid Landman, N.H., Tsujita, C.J., Cobban, W.A., Larson, N.L. from the Late Cretaceous (Turonian) of Hokkaido (Ja- & Tanabe, K. (2006): Jaws of Late Cretaceous placen- pan). – Paleontological Research, 14: 1-10. ticeratid ammonites: how preservation affects the in- Fuchs, D. & Weis, R. (2010): Taxonomy, morphology and terpretation of morphology. – The American Museum phylogeny of teudopseid coleoids (Cephalopoda). – Novitates, 3500: 1-48. Neues Jahrbuch für Geologie und Paläontologie, Ab- Lehmann, U. (1976): Ammoniten. Ihr Leben und ihre handlungen, 257: 351-366. Umwelt. – 171 pp.; Stuttgart (Enke). Fukuda, Y. (1980): Observations by SEM. – In: Hamada, T., Lehmann, U. (1980): Ammonite jaw apparatus and soft Obata, I. & Okutani, T. (Eds.): Nautilus macromphalus parts. – In: House, M.R. & Senior, J.R. (Eds.): The Am- in Captivity, 23-33; Tokyo (Tokai University Press). monoidea, 275-287; London (Academic Press). Gupta, N.S., Briggs, D.E.G., Landman, N.H., Tanabe, K. & Lehmann, U. (1990): Ammonoideen. – 257 pp.; Stuttgart Summons, R.E. (2008): Molecular structure of organic (Enke). components in cephalopods: Evidence for oxidative Lowenstam, H.A., Tarub, W. & Weiner, S. (1984): Nautilus cross linking in fossil marine invertebrates. – Organic hard parts: a study of the mineral and organic composi- Geochemistry, 39: 1405-1414. tions. – Paleobiology, 10: 269-279. Hunt, S. & Nixon, M. (1981): A comparative study of pro- Naef, A. (1921): Das System der Dibranchiaten Cephalo- tein composition in the chitin-protein complexes of the poden und die mediteranen Arten derselben. – Mit- beak, pen, sucker disc, radula and oesophageal cuticle of teilungen aus der zoologischen Station zu Neapel, 22: cephalopods. – Comparative Biochemistry and Physiol- 527-542. ogy, 68B: 535-546. Neige, P. & Dommergues, J.-L. (2002): Disparity of beaks Iba, Y., Mutterlose, J., Tanabe, K., Sano, S., Misaki, A. & and statoliths of some coleoids: A morphometric ap- Tereda, K. (2011): Belemnite extinction and the origin proach to depict shape differentiation. – In: Summes- of modern cephalopods 35 my prior to the K-P event. – berger, H., Histon, K. & Daurer, A. (Eds.): Cephalo- Geology, 39: 483-486. pods – Present and Past. – Abhandlungen der Geolo- Kerr, J.G. (1931): Notes upon the Dana specimens of Spir- gischen Bundesanstalt, 57: 393-399. ula and upon certain problems of cephalopod morphol- Okutani, T. & Mikami, S. (1977): Description on beaks of ogy. – The Danish “Dana Expeditions 1920-22 Reports, Nautlus macromphalus Sowerby. – Venus (Japanese 8: 1-34. Journal of Malacology), 36: 115-121. Klug, C. (2001): Functional morphology and taphonomy Raven, C.P. (1958): Morphogenesis: The analysis of Mollus- of nautiloid beaks from the Middle Triassic of southern can Development. – 311 pp.; Oxford (Pergamon Press). Germany. – Acta Palaeontologica Polonica, 46:43-68. Saunders, W.B., Spinosa, C., Teichert, C. & Banks, R.C. Klug, C. & Jerjen, I. (2012): The buccal apparatus with rad- (1978): The jaw apparatus of Recent Nautilus and its pal- ula of a ceratitic ammonoid from the German Middle aeontological implications. – Palaeontology, 21: 129-141. Triassic. – Géobios, 45: 57-65. Published online Decem- Starobogatov, Y.I. (1983): The System of the Cephalopoda. ber 2011; DOI: 10.1016/j.geobios.2011.12.001. – In: Starobogatov, Y.I. & Neiss, K.N. (Eds.): Taxono- Klug, C., Schweigert, G. & Dietl, G. (2010a): A new Plesi- my and Ecology of Cephalopoda, 4-7; Leningrad (Zoo- oteuthis with beak from the Kimmeridgian of Nusplin- logical Institute, USSR Academy of Sciences). gen (Germany). – In: Fuchs, D. (Ed.): Proceedings of Tanabe, K. & Fukuda, Y. (1983): Buccal mass structure of the 3rd International Symposium Coleoid Cephalopods the Cretaceous ammonite Gaudryceras. – Lethaia, 16: Through Time. – Ferrantia, 59: 73-77. 249-256. Klug, C., Schweigert, G., Dietl, G. & Fuchs, D. (2005): Tanabe, K. & Fukuda, Y. (1987): Mouth part histology and Coleoid beaks from the Nusplingen Lithographic Lime- morphology. – In: Saunders, W.B. & Landman, N.H. stone (Upper Kimmeridgian, SW Germany). – Lethaia, (Eds.): Nautilus. The Biology and Paleobiology of a Liv- 38: 173-192. ing Fossil, 313-322; New York (Plenum Press). 18 K. Tanabe

Tanabe, K. & Fukuda, Y. (1999): Morphology and func- Tanabe, K., Trask, P., Ross, R. & Hikida, Y. (2008): Late tion of cephalopod buccal mass. – In: Savazzi, E. (Ed.): Cretaceous octobrachiate coeloid jaws from the circum- Functional Morphology of the Invertebrate Skeleton, North Pacific regions. – Journal of Paleontology, 82: 245-262; London (Wiley). 429-439. Tanabe, K. & Hikida, Y. (2010): Jaws of a new species of Young, J.Z. (1993): The muscular hydrostatic radula sup- Nanaimoteuthis (Coleoidea: Vampyromorphida) from ports of Octopus, Loligo, Sepia and Nautilus. – Journal the Turonian of Hokkaido, Japan. – Paleontological Re- of Cephalopod Biology, 2: 65-93. search, 14: 145-150. Tanabe, K., Hikida, Y. & Iba, Y. (2006): Two coleoid jaws Manuscript received: February 27th, 2012. from the Upper Cretaceous of Hokkaido, Japan. – Jour- Revised version accepted: April 29th, 2012. nal of Paleontology, 80: 138-15. Tanabe, K. & Landman, N.H. (2002): Morphological di- Address of the author: versity of the jaws of Cretaceous Ammonoidea. – In: Summesberger, H., Histon, K. & Daurer, A. (Eds.): Kazushige Tanabe, Department of Earth and Planetary Cephalopods-Present and Past. – Abhandlungen der Science, The University of Tokyo, Hongo 7-3-1, Tokyo Geologischen Bundesanstalt, 57: 157-165. 113-0033, Japan; Tanabe, K., Landman, N.H. & Kruta, I. (2012): Micro- e-mail: [email protected] structure and mineralogy of the outer calcareous layer Present address: Department of Historical Geology and in the lower jaws of Cretaceous Tetragonitoidea and Palaeontology, The University Museum, The University of Desmoceratoidea (Ammonoidea). – Lethaia, 45: 191- Tokyo, Hongo 7-3-1, Tokyo 113-0033, Japan; 199. Published online May 2011; DOI::10.1111/j.1502- e-mail: [email protected] 3931.2011.00272.x