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1

Size and maturity differences between trawl and jigger caught short-finned squid Illex argentinus [Cephalopoda: Ommastrephidae]

100%

Koronkiewicz A.

Acta Ichthyologica et Piscatoria

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1995

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tom 25

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nr 1

97-112

The present study was undertaken to cast some light on this methodological problem as well as to determine how representative the materials used in biological research on Illex argentinus have been so far. It is contended that trawling, as a forced sampling technique, provides a sample representative of an Illex population, while jigging, as a harvesting/sampling method based on behavioural responses of the squids, is selective. The squids were obtained during commercial trawling and jigging operations undertaken on 4-15, 24-25 and 28-31 March and 2, 7-11 April 1992 in the Illex-rich Falkland Interim Conservation Zone. Differences among basic biological parameters of the population (e.g. length and maturity frequency) indicate that jigger-caught Illex were larger than those caught by trawling by 7 mm (males) and 12 mm (females) on the average. Jiggers affected the behavioural responses of the squids and resulted in higher frequencies of larger individuals. Those frequencies being higher by: 13.5% in 25-28 cm long males, the general range being 19-28 cm; 21.2% in 26-30 cm long females, the general range being 16-30 cm. Differences between the jigger-and trawl-caught squid lengths can be described with a linear regression. The jigger-caught Illex were more mature than those caught with the trawl by 0.8% (males) and 5.1% (females), on the average.

2

Genetic identification of a rare record of Ommastrephes bartramii (Cephalopoda: Ommastrephidae) from the Eastern Adriatic Sea

100%

Franjevic D., Skaramuca D., Katavic V., Rajevic N., Skaramuca B.

Folia Biologica

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2015

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tom 63

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nr 1

3

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Minute Silurian oncocerid nautiloids with unusual colour patterns

84%

Manda S., Turek V.

Acta Palaeontologica Polonica

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2009

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tom 54

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nr 3

503-512

A minute Silurian oncocerid Cyrtoceras pollux, from the Prague Basin is assigned here to the genus Pomerantsoceras. The only so far known species of this genus comes from the Upper Ordovician (Hirnantian) of Estonia. Pomerantsoceras thus represents, except for un−revised poorly understood taxa, the single known oncocerid genus surviving the end−Ordovician extinction events. Cyrtoceras pollux is unusual among the Silurian nautiloids because of its small shell. Colour pattern characterised by a few longitudinal bands on the entire circumference of the shell is here reported in oncocerids. Longicone and only slightly curved small shells as in Pomerantsoceras are unusual among nautiloids and resemble straight shells of orthocerids and pseudorthocerids, in which the colour pattern consists of straight colour bands. Consequently the shell shape as well as the colour pattern should be regarded as adaptive convergence with orthocerids and pseudorthocerids. It supports the hypothesis that colour pattern functioned as camouflage and its evolution was under adaptive control. In addition, several types of the shell malformations including anomalous growth of septa, shell wall and pits on an internal mould are described.

4

A review of the endocerid cephalopod Protocyptendoceras from the Floian [Lower Ordovician] of the Eastern Cordillera, Argentina

84%

Cichowolski M.

Acta Palaeontologica Polonica

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2009

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tom 54

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nr 1

99-109

Ordovician cephalopods from Western Gondwana are still poorly known and published data is in need of systematic and stratigraphical revision. In this work, the endocerid proterocameroceratid Protocyptendoceras from the Floian of the Eastern Cordillera of Argentina is revised using new material from La Ciénaga, 5 km upstream from Purmamarca. The species P. corvalani and P. teicherti are considered to be junior synonyms of P. fuenzalidae, which is redescribed in detail and reillustrated. Specimens preserve adapical parts of isolated siphuncles, related here to the presence of endocones in a posterior portion. Evidently P. fuenzalidae had a nektobenthic mode of life in a shallow water environment, oriented horizontally. Its palaeobiogeographical affinities are mainly with Floian proterocameroceratids from Eastern Gondwana, such as Anthoceras decorum and the related genera Lobendoceras, Ventroloboceras, and Notocycloceras.

5

Size-shape relationships in the Mesozoic planispiral ammonites

84%

Parent H., Greco A. F., Bejas M.

Acta Palaeontologica Polonica

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2010

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tom 55

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nr 1

Ammonites are of outstanding importance in dating events of the Mesozoic and in the study of mechanisms, modes and timing of evolutionary processes. These applications rely on a detailed understanding of their morphology and the modes of variation. It has been known for a long time that their shape is composed of a number of highly correlated features. A new model, called the ADA−model, is introduced for the study of shell morphology (size and shape). The new model is based on classic dimensions which are stable parameters throughout ontogeny, giving very close agreement between pre− dictions and actual observations. It was applied in the exploration of the morphospace occupied by the planispirally coiled and the regularly uncoiled Mesozoic Ammonoidea, based on two new reduced morphospaces introduced for the analysis. Results obtained expose close relationships between size and shape, and general patterns in the ammonite shell morphol− ogy and morphogenesis. (i) The relative apertural height of the whorl section relative to the diameter of the shell (H₂/D) is involved in definition of size and shape. (ii) This same dimension shows a strong tendency to be H₂/D = 0.3. (iii) There are some geometrically possible shell shapes (or morphotypes) which seem to have not been developed since they are not known in the current record. Assuming the known ranges of protoconch size and whorl number as constraints, the ADA−model strongly suggests that these morphotypes have not been developed for the too large or too small sizes the shells would have attained, well outside of the actual size range of the planispirally coiled Ammonoidea. (iv) The law of covariation is shown to be a general pattern within the planispiral ammonites which describes structured variation of the shell shape. (v) A large fraction of the non−structured variation seems originate in the lack of correlation between the rela− tive umbilical diameter and width of the whorl section.

6

A rare coleoid mollusc from the Upper Jurassic of Central Russia

84%

Doguzhaeva L. A.

Acta Palaeontologica Polonica

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2000

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tom 45

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nr 4

The shell of the coleoid cephalopod mollusc Kostromateuthis roemeri gen. et sp. n. from the lower Kimmeridgian of Central Russia consists of the slowly expanding orthoconic phragmocone and aragonitic sheath with a rugged surface, a weakly developed post-alveolar part and a long, strong, probably dorsal groove. The sheath lacks concentric structure common for belemnoid rostra. It is formed by spherulites consisting of the needle-like crystallites, and is characterized by strong porosity and high content of originally organic matter. Each spherulite has a porous central part, a solid periphery and an organic cover. Tubular structures with a wall formed by the needle-like crystallites are present in the sheath. For comparison the shell ultrastructure in Recent Spirula and Sepia, as well as in the Eocene Belemnosis were studied with SEM. Based on gross morphology and sheath ultrastructure K. roemeri is tentatively assigned to Spirulida and a monotypic family Kostromateuthidae nov. is erected for it. The Mesozoic evolution of spirulids is discussed.

7

Concentrations of Silurian nautiloid cephalopods from Russia and Kazakhstan

84%

Bogolepova O. K., Holland C. H.

Acta Palaeontologica Polonica

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1995

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tom 40

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nr 4

Silurian cephalopod limestones known from northern Asia are usually singular beds or horizons of nodules. They range in their taphonomic character from the Mojero river type, with postmortem concentration from rich living populations by relatively gentle bottom currents into a submarine low, to that of the Karabutak Formation of the South Urals, where there has been concentration by strong wave or current action.

8

Cephalopods (Mollusca: Cephalopoda) in the palaeontological collection of the Faculty of Biology, Adam Mickiewicz University

67%

Konwerski S., Bloszyk J.

Folia Malacologica

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2012

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tom 20

|

nr 1

9

Molluscs of the Polish Baltic

67%

Piechocki A., Wawrzyniak-Wydrowska B.

Folia Malacologica

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2012

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tom 20

|

nr 1

10

Extreme abundance of ammonoids in mass accumulations from the Late Devonian of the Moroccan Anti-Atlas

67%

Greif M., Nebelsick J. H., Klug C.

Acta Palaeontologica Polonica

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2022

|

tom 67

|

nr 3

11

Triassic coleoid beaks and other structures from the Calcareous Alps revisited

67%

Doguzhaeva L. A., Summesberger H., Brandstaetter F., Gruber D., Tintori A.

Acta Palaeontologica Polonica

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2022

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tom 67

|

nr 3

12

Colour patterns in Early Devonian cephalopods from the Barrandian Area: Taphonomy and taxonomy

67%

Turek V.

Acta Palaeontologica Polonica

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2009

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tom 54

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nr 3

491-502

Five cephalopod specimens from the Lower Devonian of Bohemia (Czech Republic) preserve colour patterns. They include two taxonomically undeterminable orthoceratoids and three oncocerid nautiloids assigned to the genus Ptenoceras. The two fragments of orthocone cephalopods from the lowest Devonian strata (Lochkovian, Monograptus uniformis Zone) display colour patterns unusual in orthoceratoids. They have irregular undulating and zigzag strips that are preserved on counterparts of adapertural regions of specimens flattened in shale, despite their original aragonitic shell having been completely dissolved. These are probably the result of the proteinous pigment inside the shell wall, being substituted during diagenesis by secondary minerals leaving only an altered trace of the original shell. Orthoceratoids from sediments unsuitable for preservation of this feature discussed here thus demonstrate an exceptional case of preservation of colour patterns, not only within Devonian cephalopods but also within other Devonian molluscs. Three specimens of Ptenoceras that preserve colour patterns come from younger Lower Devonian strata. Oblique spiral adaperturally bifurcating bands are preserved in P. alatum from the Pragian and zigzags in P. nudum from the Dalejan. Juvenile specimen of Ptenoceras? sp. from the Pragian exhibits highly undulating transversal bands—a pattern resembling colour markings in some Silurian oncocerids. Dark grey wavy lines observed on the superficially abraded adapical part of a phragmocone of nautiloid Pseudorutoceras bolli and interpreted formerly to be colour markings are here reinterpreted as secondary pigmented growth lines. Other Devonian fossils including a single brachiopod and several gastropods from the Barrandian Area with preserved colour patterns are mentioned. Variety of cephalopod colour patterns, their taxonomic significance, function and significance for palaeoecological interpretation, palaeoenvironmental conditions favouring colour pattern preservation and systematic affiliation of taxa with colour pattern preserved are discussed.

13

Late Cretaceous record of large soft-bodied coleoids based on lower jaw remains from Hokkaido, Japan

67%

Tanabe K., Misaki A., Ubukata T.

Acta Palaeontologica Polonica

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2015

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tom 60

|

nr 1

The origin and phylogenetic relationships of most modern coleoid groups have not yet been explained by reliable fossil evidence, in large part because of the reduction or disappearance of a calcified chambered shell during their evolutionary history. Herein we describe two exceptionally large coleoid lower jaws from the Upper Cretaceous strata in Hokkaido, Japan. On the basis of the comparison of gross morphology and morphometric data of the lower jaws of modern and fossil coleoids, we assigned the two lower jaws to the following new taxa: Nanaimoteuthis hikidai sp. nov. of the order Vampyromorpha (superorder Octobrachia) and Haboroteuthis poseidon gen. et sp. nov. of the order Teuthida (superorder Decabrachia). The lower jaw of N. hikidai is distinguished from other species of the same genus from the Upper Cretaceous of Vancouver Island (Canada) and Hokkaido by having a broader, more anteriorly curved hood of the outer lamella. The lower jaw of H. poseidon seemingly exhibits mosaic features like those of modern teuthids and sepiids but is assigned to Teuthida on the basis of the overall shape of the outer lamella and the development of a distinct fold on the lateral wall. Because of the unusually large lower jaws, these new taxa appear to be comparable in body size to modern giant squids (Architeuthis spp.) and the Humboldt squid (Dosidicus gigas). This and other discoveries of large jaws referable to octobrachian and decabrachian coleoids from the Upper Cretaceous strata of the North Pacific fill the gap in the relatively poor fossil record of mainly soft-bodied coleoids.

14

Concentration of juvenile and small cephalopods in the Hirnantian cherts [Late Ordovician] of Porkuni, Estonia

67%

Kroger B.

Acta Palaeontologica Polonica

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2007

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tom 52

|

nr 3

The quarry in the north Estonian village of Porkuni provides a succession of shallow−water limestones and cherts spanning the Ashgillian Normalograptus? extraordinarius graptolite Biozone. This interval comprises the initial pulse of the end−Ordovician extinction. The succession of Porkuni contains abundant and extraordinarily well−preserved fossils. 71 cephalopod specimens were extracted from these strata at Porkuni. Many of these specimens are fragments of juvenile shells or small adults. The embryonic shells of the cephalopods are usually preserved and provide insight into their early ontogeny. The faunal composition is considered as autochthonous and reflects a “palaeo−nursery” in a Hirnantian reef environment. The collected specimens represent twelve genera and four orders. Small oncoceridans and orthoceridans dominate the association. The rate of endemism is very high, since only two genera found in Porkuni, are known from outside Baltoscandia. The new genera Parvihebetoceras, Pomerantsoceras, Porkunioceras, and the new species Parvihebetoceras wahli, Pomerantsoceras tibia, Porkunioceras tuba, and Strandoceras orvikui are erected.

15

Soft-tissue attachments in orthocerid and bactritid cephalopods from the Early and Middle Devonian of Germany and Morocco

67%

Kroger B., Klug C., Mapes R.

Acta Palaeontologica Polonica

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2005

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tom 50

|

nr 2

In the Early to Middle Devonian shale sequences of Germany and Morocco, pyritised and secondarily limonitised cephalopod remains are common. Details of the soft−tissue attachment structures are sometimes preserved on the internal moulds of the body chamber and phragmocone of these cephalopods. Some of the studied Orthocerida show a very faint annular elevation and a dorsal furrow. A few Bactritida show a distinctive annular elevation with two circular bands. The bands form a paired or threefold lobe at the dorsum of the shell. Morphological differences between Orthocerida and Bactritida suggest different soft part morphologies. A comparison of the attachment scars shows that the Bactritida are intermediate between the Orthocerida and ammonoids with regard to their muscle attachment scars. The shape of the muscle scars are interpreted as indication for a planktonic lifestyle in Orthocerida and a comparatively active, nektonic lifestyle in Bactritida and ammonoids. The new genus Acanthomichelinoceras is erected. Acanthomichelinoceras commutatum, Cycloceras sp., Bactrites gracile, Bactrites sp. A, Bactrites sp. B, and Bactrites sp. C are described.

16

Revision of Middle Ordovician orthoceratacean nautiloids from Baltoscandia

67%

Kroger B.

Acta Palaeontologica Polonica

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2004

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tom 49

|

nr 1

The fauna of the Baltoscandic Orthocerataceae is important because it fills a documentary gap between the Lower Ordovician fauna of North America and the upper Middle Ordovician fauna of China and North America. A revision of the Orthoceratidae, Geisonoceratidae, and Arionoceratidae is given on a material of more than 450 specimens. Intraspecific and ontogenetic variations were observed. The following new taxa are erected: Plagiostomoceras fragile sp. nov., Archigeisonoceras repplingense sp. nov., Archigeisonoceras picus sp. nov. Archigeisonoceras folkeslundense sp. nov., Nilssonoceras latisiphonatum gen. et sp. nov., Kinnekulloceras kinnekullense gen. et sp. nov., and Arionoceras lotskirkense sp. nov. The genus Archigeisonoceras is described for the first time in the Baltoscandic area and the oldest occurrence of the genus Arionoceras is documented from the Middle Ordovician of Baltoscandia. It is shown that the endosiphuncular deposits of the Middle Ordovician orthoceratacaceans are highly variable and widespread in the apical parts of the phragmocone.

17

Preliminary description of two new species of cephalopods [Cephalopoda: Brachioteuthidae] from South Atlantic and Antarctic waters

67%

Lipinski M. R.

Bulletin of the Sea Fisheries Institute

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2001

|

nr 1

18

Gladius shape variation in coleoid cephalopod Trachyteuthis from the Upper Jurassic Nusplingen and Solnhofen Plattenkalks

67%

Fuchs D., Engeser T., Keupp H.

Acta Palaeontologica Polonica

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2007

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tom 52

|

nr 3

Although the fossil record of coleoid cephalopods is generally poor, the Upper Jurassic Nusplingen and Solnhofen Plattenkalks have provided numerous well−preserved coleoids. Trachyteuthis hastiformis, a comparatively large vampyropod coleoid, was previously known to represent the sole species of its genus in Nusplingen and Solnhofen. However, morphological comparisons based on 50 specimens from different museum collections revealed two additional species: T. nusplingensis sp. nov. and T. teudopsiformis sp. nov. Both species lack the distinct spindle−shaped elevation on the gladius median field typical for T. hastiformis. T. nusplingensis sp. nov. is clearly characterised by a smooth median field and a more or less regular granulation on the dorsal gladius surface, whereas T. teudopsiformis sp. nov. can be easily distinguished by the presence of a Teudopsis−like median keel and an extremely narrow granulation. Morphometric analyses have shown that length−width indices are ambiguous characters to differentiate between the three species. Phylogenetically, the keeled and anteriorly pointed T. teudopsiformis sp. nov. can be linked with the Early Jurassic genus Teudopsis and the Late Cretaceous genus Glyphiteuthis.

19

Aragonitic rostra of the Turonian belemnitid Goniacamax: arguments from diagenesis

59%

Dauphin Y., Williams C. T., Barskov I. S.

Acta Palaeontologica Polonica

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2007

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tom 52

|

nr 1

The hypothesis that belemnitid rostra are formed by primary biogenic low−Mg calcite is widespread. However, the coexistence in the same rostrum of both aragonitic and calcitic components has been reported in true belemnites (Goniocamax, Turonian). A combined microstructural and chemical composition study of the comparison of shells with undisputed mineralogy from the same site as the Turonian Goniocamax, shows that these aragonitic shells display the effects of diagenetic alteration. These observations favour the hypothesis that belemnite rostra are composed of primary aragonite, rather than low−Mg calcite, and are consistent with all other cephalopod shells. Calcitic and aragonitic rostra are also known in other Dibranchiata such as Triassic Aulacocerida and Eocene Belopterina. Diagenetic changes such as shown here may clearly affect palaeo−environmental interpretations based on carbonate shells.

20

Owoce morza - czesc II: skorupiaki i glowonogi

51%

Kolanowski W.

Magazyn Przemysłu Rybnego

|

2003

|

nr 5

37-40

Ograniczanie wyników

Size and maturity differences between trawl and jigger caught short-finned squid Illex argentinus [Cephalopoda: Ommastrephidae]

Genetic identification of a rare record of Ommastrephes bartramii (Cephalopoda: Ommastrephidae) from the Eastern Adriatic Sea

Minute Silurian oncocerid nautiloids with unusual colour patterns

A review of the endocerid cephalopod Protocyptendoceras from the Floian [Lower Ordovician] of the Eastern Cordillera, Argentina

Size-shape relationships in the Mesozoic planispiral ammonites

A rare coleoid mollusc from the Upper Jurassic of Central Russia

Concentrations of Silurian nautiloid cephalopods from Russia and Kazakhstan

Cephalopods (Mollusca: Cephalopoda) in the palaeontological collection of the Faculty of Biology, Adam Mickiewicz University

Molluscs of the Polish Baltic

Extreme abundance of ammonoids in mass accumulations from the Late Devonian of the Moroccan Anti-Atlas

Triassic coleoid beaks and other structures from the Calcareous Alps revisited

Colour patterns in Early Devonian cephalopods from the Barrandian Area: Taphonomy and taxonomy

Late Cretaceous record of large soft-bodied coleoids based on lower jaw remains from Hokkaido, Japan

Concentration of juvenile and small cephalopods in the Hirnantian cherts [Late Ordovician] of Porkuni, Estonia

Soft-tissue attachments in orthocerid and bactritid cephalopods from the Early and Middle Devonian of Germany and Morocco

Revision of Middle Ordovician orthoceratacean nautiloids from Baltoscandia

Preliminary description of two new species of cephalopods [Cephalopoda: Brachioteuthidae] from South Atlantic and Antarctic waters

Gladius shape variation in coleoid cephalopod Trachyteuthis from the Upper Jurassic Nusplingen and Solnhofen Plattenkalks

Aragonitic rostra of the Turonian belemnitid Goniacamax: arguments from diagenesis

Owoce morza - czesc II: skorupiaki i glowonogi