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1
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A probable stegosaurian track from the Late Jurassic of Poland

100%
Gierlinski G., Sabath K.
Acta Palaeontologica Polonica
|
2002
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tom 47
|
nr 3
Elusive tracks of stegosaurs have been long searched for by ichnologists, and various purported stegosaur imprints have recently been reported. A fragmentary trackway of a large, quadrupedal ornithischian dinosaur was found on an isolated slab of Oxfordian dolomite, on the northeastern slope of Holy Cross Mountains, Poland. The track is similar to large, blunt−toed Late Jurassic ichnites from North America. The footprints show a distinctive morphology, which fits the stegosaurian foot. The newly described ichnites from the Upper Jurassic of Poland provide the second ichnological evidence of the Late Jurassic dinosaurs in this country; numerous rich dinosaur footprint assemblages were previously known only from the Lower Jurassic outcrops.
2
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The oldest representative of a modern deep-sea ophiacanthid brittle-star clade from Jurassic shallow-water coral reef sediments

72%
Thuy B., Schulz H.
Acta Palaeontologica Polonica
|
2013
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tom 58
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nr 3
Ophiurites crinitus is a fossil brittle−star species which passed largely unnoticed since its original description. In this paper, we redescribe the type material of O. crinitus with the aim to put it into the context of modern ophiuroid systematics, and propose the new genus name Ophiosternle to replace the invalid Ophiurites. The re−assessed species is shown to be a member of the extant deep−sea family Ophiacanthidae, articulated fossils of which are extremely rare. It presents greatest affinities with members of the Ophioplinthaca–Ophiocamax–Ophiomitra clade, of which it most probably represents the oldest known fossil species. The depositional environment of the strata, which yielded the described specimens is interpreted as shallow, storm−influenced marine setting in the immediate vicinity of coral reefs. This contrasts with the distribution pattern of extant species of the Ophioplinthaca–Ophiocamax–Ophiomitra clade, which almost exclusively occur at depths exceeding the shelf break.
3
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Foraminiferal assemblages as palaeoenvironmental bioindicators in Late Jurassic epicontinental platforms: Relation with trophic conditions

72%
Reolid M., Nagy J., Rodriguez-Tovar F. J., Oloriz F.
Acta Palaeontologica Polonica
|
2008
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tom 53
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nr 4
Foraminiferal assemblages from the neritic environment reveal the palaeoecological impact of nutrient types in relation to shore distance and sedimentary setting. Comparatively proximal siliciclastic settings from the Boreal Domain (Brora section, Eastern Scotland) were dominated by inner−shelf primary production in the water column or in sea bottom, while in relatively seawards mixed carbonate−siliciclastic settings from the Western Tethys (Prebetic, Southern Spain), nutrients mainly derived from the inner−shelf source. In both settings, benthic foraminiferal assemblages increased in diversity and proportion of epifauna from eutrophic to oligotrophic conditions. The proximal setting example (Brora Brick Clay Mb.) corresponds to Callovian offshore shelf deposits with a high primary productivity, bottom accumulation of organic matter, and a reduced sedimentation rate for siliciclastics. Eutrophic conditions favoured some infaunal foraminifera. Lately, inner shelf to shoreface transition areas (Fascally Siltstone Mb.), show higher sedimentation rates and turbidity, reducing euphotic−zone range depths and primary production, and then deposits with a lower organic matter content (high−mesotrophic conditions). This determined less agglutinated infaunal foraminifera content and increasing calcitic and aragonitic epifauna, and calcitic opportunists (i.e., Lenticulina). The comparatively distal setting of the Oxfordian example (Prebetic) corresponds to: (i) outer−shelf areas with lower nutrient input (relative oligotrophy) and organic matter accumulation on comparatively firmer substrates (lumpy lithofacies group) showing dominance of calcitic epifaunal foraminifera, and (ii) mid−shelf areas with a higher sedimentation rate and nutrient influx (low−mesotrophic conditions) favouring potentially deep infaunal foraminifers in comparatively unconsolidated and nutrient−rich substrates controlled by instable redox boundary (marl−limestone rhythmite lithofacies).
4
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Functional anatomy and mode of life of the latest Jurassic crinoid Saccocoma

72%
Brodacki M.
Acta Palaeontologica Polonica
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2006
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tom 51
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nr 2
Loose elements of the roveacrinid Saccocoma from the Tithonian red Rogoża Coquina, Rogoźnik, Pieniny Klippen Belt, Poland, are used to test the contradictory opinions on the mode of life of Saccocoma. The investigated elements belong to three morphological groups, which represent at least two separate species: S. tenella, S. vernioryi, and a third form, whose brachials resemble those of S. vernioryi but are equipped with wings of different shape. The geometry of brachials’ articular surfaces reveals that the arms of Saccocoma were relatively inflexible in their proximal part and left the cup at an angle of no more than 45, then spread gradually to the sides. There is no evidence that the wings were permanently oriented in either horizontal or vertical position, as proposed by two different benthic life−style hypotheses. The first secundibrachial was probably more similar to the first primibrachial than to the third secundibrachial, in contrast to the traditional assumption. The winged parts of the arms were too close to the cup and presumably too stiff to propel the animal in the water efficiently. Swimming was probably achieved by movements of the distal, finely branched parts of the arms. The nonhorizontal attitude of the winged parts of the arms is also not entirely consistent with the assumption that they functioned as a parachute. Moreover, the wings added some weight and thus increased the energy costs associated with swimming. The hydrodynamic benefits balancing these extra costs are not entirely clear, but it seems probable that the wings reduced the sinking rate of the animal not by increasing the pressure drag, as suggested by the parachute−analogy, but by increasing the surface drag (friction drag), which also harmonize with the presence of spines, reticulate sculpture and conspicuous vacuolar ornamentation in some species of Saccocoma.
5
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Middle and Late Jurassic tube-dwelling polychaetes from the Polish Basin: diversity, palaeoecology and comparisons with other assemblages

58%
Slowinski J., Vinn O., Jager M., Zaton M.
Acta Palaeontologica Polonica
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2022
|
tom 67
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nr 4
6
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Velociraptorine dromaeosaurid teeth from the Kimmeridgian [Late Jurassic] of Germany

58%
van der Lubbe T., Richter U., Knotschke N.
Acta Palaeontologica Polonica
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2009
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tom 54
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nr 3
401-408
Six theropod teeth from a Late Jurassic (Kimmeridgian) bone bed in Langenberg Quarry of Oker (Goslar, Germany) are identified as a new dromaeosaurid taxon, here left in open nomenclature. Direct comparison reveals that the teeth are very similar to velociraptorine dromaeosaurid teeth from the Guimarota coal mine (Late Jurassic, Portugal) and to velociraptorine dromaeosaurid teeth from Uña (Barremian, Cuenca Province, Spain). Our data indicate that the teeth from the Kimmeridgian of Lower Saxony are of velociraptorine dromaeosaurid type, and therefore represent one of the oldest occurrences of the group Dromaeosauridae.
7
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Ecophenotypic plasticity versus evolutionary trends - morphological variability in Upper Jurassic bivalve shells from Portugal

58%
Schneider S., Fursich F. T., Schulz-Mirbach F. T., Werner W.
Acta Palaeontologica Polonica
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2010
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tom 55
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nr 4
Upper Jurassic marginal marine strata of the Lusitanian Basin (central Portugal) yield a rich benthic macrofauna from which three bivalve target taxa, i.e., Arcomytilus, Isognomon, and Eomiodon, were chosen for morphometric studies, because of their abundance both in space and time and their variability in shell shape. The shells have been analysed with regard to outline shape (Fourier shape analysis), dimensions, ornamentation (Arcomytilus) and ligament arrangement (Isognomon). Additionally, data on co−occurring fauna and palaeotemperatures calculated from δ18O values have been recorded. The results of the morphometric analyses have been interpreted with regard to phylogeny and palaeoecology. In all target taxa, a distinct, rapid size increase at around the Early/Late Kimmeridgian boundary is evident. Potential causes for this process are discussed, and an increase in food availability is regarded the most likely scenario. In Isognomon rugosus, a distinct change in resilifer arrangement co−occurs with size increase, resulting in the evolution of an endemic species in the Lusitanian Basin, for which the name Isognomon lusitanicus is reestablished. Like in several extant Mytilidae, morphological species characterisation in Arcomytilus turns out unsatisfactory, due to high intraspecific variability. However, Arcomytilus morrisii is still regarded as a valid species that evolved in the Lusitanian Basin. Despite high shape variability, Eomiodon securiformis is also considered to be a clearly distinguished species. For all target taxa morphologic variability is discussed with regard to environment, and variation between populations is delineated. The data suggest a weak correlation of facies and shell shape in Arcomytilus, while Isognomon lusitanicus seems to develop local varieties in different subbasins. Finally, the great morphologic plasticity of bivalves from rather distinct systematic entities is shown to result from different causes, thus demonstrating that careful studies of the involved species are a prerequisite to draw correct palaeoecological conclusions.
8
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New Lower Kimmeridgian ataxioceratin ammonite from the eastern Iberian Chain, Spain: Systematic, biogeographic, and biostratigraphic relevance

58%
Moliner L., Oloriz F.
Acta Palaeontologica Polonica
|
2010
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tom 55
|
nr 1
New ammonites collected bed−by−bed from the upper part of Ataxioceras hypselocyclum Chronozone deposits in the eastern Iberian Chain are described as Geyericeras gen. nov. The new genus includes microand macroconchiate Ataxioceratinae of small size, with moderate to loose coiling and subpolyplocoid ribs, a character crucial for its identification. Key points for the comparative identification of Geyericeras gen. nov. are: (i) microconchiate Geyericerasshow morphological convergence with evolute specimens of the stratigraphically older genus Schneidia [m]; (ii) contemporary Ataxioceratinae genera such as Ardescia [m, M] and Lithacosphinctes [m, M] did not develop subpolyplocoid ribbing; (iii) smoothing of sculpture combined with short primary ribs are not realized in Geyericeras gen. nov. [M] and can be therefore used to separate the new genus from Ataxioceras[M]; and (iv) smaller shells, and weaker and less dense ribbing with no parabolic structures differentiate Geyericeras gen. nov. [m, M] from Parataxioceras[m, M], as well as the type of subpolyplocoid ribs seen among microconchiate specimens of these two genera. The new species Geyericeras aragoniense sp. nov. is the index and guide fossil for identification of a biohorizon occurring below the first occurrence of the genus Crussoliceras in the eastern Iberian Chain.
9
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The soft-tissue attachment scars in Late Jurassic ammonites from Central Russia

58%
Mironenko A. A.
Acta Palaeontologica Polonica
|
2015
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tom 60
|
nr 4
Soft-tissue attachment scars of two genera and four species of Late Jurassic craspeditid ammonites from the Russian Platform are described. A previously suggested relationship between lateral attachment scars and ammonoid hyponome is confirmed, however, a new interpretation is proposed for dorsal attachment scars: they could have been areas not only for attachment of the dorsal (nuchal) retractors, but also of the cephalic retractors. The new type of the soft-tissue attachment—anterior lateral sinuses, located between the lateral attachment scars and the aperture of the ammonite body chamber is described. Enclosed elliptical or subtriangular areas in apertural parts of the anterior lateral sinuses were found for the first time. Their presence and location suggest that this structure could have been used for attaching the funnel-locking apparatus, similar to those of coleoids. A transformation of shape and position of lateral attachment scars through the evolution of the Late Jurassic craspeditid lineage starting from platycones (Kachpurites fulgens) to keeled oxycones (Garniericeras catenulatum) is recognized.
10
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The systematics of Late Jurassic tyrannosauroid theropods from Europe and North America

58%
Brusatte S. L., Benson R. B. J.
Acta Palaeontologica Polonica
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2013
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tom 58
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nr 1
Recent discoveries of more than ten new species of tyrannosauroid theropods are helping to understand the origin and evolu− tion of colossal body size and other characteristic features of Tyrannosaurus rex and its terminal Cretaceous relatives. Partic− ularly important has been the discovery and reinterpretation of Late Jurassic tyrannosauroids from Europe and North Amer− ica, which are intermediate in size and phylogenetic position between small basal tyrannosauroids and the largest Late Cre− taceous species. The fragmentary nature of these Jurassic specimens, however, has frustrated attempts to understand their systematics and phylogeny. A new specimen from the Late Jurassic of England was recently named as a new species (Stokesosaurus langhami) of the genus Stokesosaurus, which is known from several fragmentary fossils from North Amer− ica. We review the systematics and phylogeny of these European and North American specimens and show that there are no unequivocal synapomorphies uniting them. Furthermore, a revised phylogenetic analysis does not recover them as sister taxa. This necessitates a taxonomic revision of this material, and we name a new genus (Juratyrant) for theBritish specimen.
11
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The earliest record of pylochelid hermit crabs from the Late Jurassic of southern Poland, with notes on paguroid carapace terminology

58%
Fraaije R. H. B., Krzeminski W., Van Bakel B. W. M., Krzemiska E., Jagt J. W. M.
Acta Palaeontologica Polonica
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2012
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tom 57
|
nr 3
Strata with cyanobacterial−sponge buildups of Middle to Late Oxfordian (Late Jurassic) age in the southern Polish Uplands document the earliest known members of the Pylochelidae. Two new Late Jurassic species of “symmetrical” hermit crabs, Ammopylocheles robertboreki and Jurapylocheles iwonae, are described. A new term, the massetic region, is introduced to describe the equivalent in paguroids of the hepatic region in brachyuran carapaces, because in the former, this region does not reflect the position of the liver but rather an attachment zone of the mandibular muscles.
12
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Redescription of the type specimens for the Late Jurassic rhynchocephalian Opisthias rarus and a new specimen of Theretairus antiquus from Quarry 9, Morrison Formation, Wyoming, USA

58%
Herrera-Flores J. A., Stubbs T. L., Sour-Tovar F.
Acta Palaeontologica Polonica
|
2022
|
tom 67
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nr 3
13
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New Late Jurassic symmetrical hermit crabs from the southern Polish Uplands and early paguroid diversification

58%
Fraaije R. H. B., Krzeminski W., Van Bakel B. W. M., Krzeminska E., Jagt J. W. M.
Acta Palaeontologica Polonica
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2014
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tom 59
|
nr 3
On the basis of carapaces, three new genera and species of symmetrical paguroid anomurans are described. Diogenicheles theodorae, Masticacheles longirostris, and Pilgrimcheles karolinae constitute the oldest known members of the family Parapylochelidae. As noted previously, assemblages from sponge−reefal strata of Oxfordian (Late Jurassic) age in the south− ern Polish Uplands document an important radiation event amongst paguroids. Compared to the present day, the Parapylochelidae were more diverse during the mid−Mesozoic; they appear to have withdrawn from shallow, reefal waters to deep−water settings from the Late Jurassic onwards. Paguroid faunas from the Oxfordian of Europe already are highly di− verse, both morphologically and phylogenetically, and comprise early members of the families Diogenidae, Pylochelidae, and Parapylochelidae. This suggests that the evolutionary history of paguroids started much earlier (i.e., in pre−Jurassic times) than previously assumed. New terms for several typical paguroid carapace regions are introduced and on the basis of carapace morphology and ecological shifts hypotheses on the early speciation of hermit crabs are put forward.
14

New fossil weevils (Coleoptera: Curculionoidea: Nemonychidae) from the Jehol Biota of western Liaoning, China

58%
Liu M., Ren D., Tan J.
Annales Zoologici
|
2006
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tom 56
|
nr 4
Three new species Brenthorrhinoides latipecteris sp. nov., B. angustipecteris sp. nov., B. magnoculi sp. nov. within the family Nemonychidae (Coleoptera: Curculionoidea) are described and illustrated. All the fossils were recovered from the Yixian Formation (Late Jurassic or Early Cretaceous) of western Liaoning Province, China. A brief review of fossil nemonychids and a key to species within the genus Brenthorrhinoides are provided. Furthermore, possible host plants to these ancient nemonychids are discussed.
15

New Mesozoic cockroaches [Blattaria: Blattulidae] from Jehol Biota of Western Liaoning in China

58%
Wang T., Ren D., Liang J. H., Shih C.
Annales Zoologici
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2007
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tom 57
|
nr 3
Macaroblattula ellipsoides gen. et sp. nov., Elisama cuboides sp. nov. and E. extenuata (Ren, 1995) of the dominant cockroach family Blattulidae are described from the Late Jurassic/Early Cretaceous Yixian Formation of western Liaoning in China. Forewing venation of E. extenuata reveals low variation (CV for total number of veins = 6.22), which indicates active flight of this advanced taxon. Presence of Macaroblattula gen. nov. suggests a generic variation and high adaptability of the family. Taxonomic composition supports the transitional Late Jurassic/Early Cretaceous age of the Yixian Formation and dominance of the family Blattulidae within assemblage indicates their significance in food chain.
16
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Gigantic footprint of a theropod dinosaur in the Early Jurassic of Poland

58%
Gierlinski G., Niedzwiedzki G., Pienkowski G.
Acta Palaeontologica Polonica
|
2001
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tom 46
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nr 3
17
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Humeral torsion in multituberculate mammals

58%
Kielan-Jaworowska Z.
Acta Palaeontologica Polonica
|
1998
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tom 43
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nr 1
18
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The earliest record of a diogenid hermit crab from the Late Jurassic of the southern Polish Uplands, with notes on paguroid carapace terminology

51%
Fraaije R. H. B., Krzeminski W., Van Bakel B. W. M., Krzeminska E., Jagt J. W. M.
Acta Palaeontologica Polonica
|
2012
|
tom 57
|
nr 3
A new species of diogenid paguroid, Eopaguropsis nidiaquilae, the earliest known member of the family to date, is recorded from sponge−reefal strata of Oxfordian (Late Jurassic) age in the southern Polish Uplands. Morphological features of the carapace suggest that the family Diogenidae diverged from other paguroid lineages such as the Pylochelidae and Parapaguridae, long before the Oxfordian Stage (161.2–155.7 Ma). The typically deep, V−shaped cervical groove of diogenids most likely was the product of fusion of the branchiocardiac and cervical grooves of their predecessors.
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