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1

Śladami skamieniałych świadectw prehistorii naszego regionu - Wojkowice

100%
Trzesiok D., Wieczorek A., Trzesiok S., Brachaniec T.
Przyroda Górnego Śląska
|
2016
|
nr 84
2

Immune phenomena in echinoderms

100%
Glinski Z., Jarosz J.
Archivum Immunologiae et Therapiae Experimentalis
|
2000
|
tom 48
|
nr 3
3
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The oldest isorophid edrioasteroid [Echinodermata] and the evolution of attachment strategies in Cambrian edrioasteroids

84%
Zamora S., Smith A. B.
Acta Palaeontologica Polonica
|
2010
|
tom 55
|
nr 3
487-494
Two new middle Cambrian edrioasteroid (Echinodermata), Protorophus hispanicus gen. et sp. nov., and Isorophida gen. et sp. indet., are described from the early middle Cambrian (Cambrian Series 3, Stage 5) of Spain. These are the oldest and probably the most primitive isorophids, a clade previously known from the upper Cambrian onwards. Specimens are attached to trilobite fragments indicating that edrioasteroids had by this time separated into two lineages each with different strategies for attachment, sediment attachers and hard substrate attachers. The single U−shaped ambulacral flooring plates of Protorophus are unique while Isorophida gen. et sp. indet. shares the presence of spines in common with some pyrgocystitid isorophids. The shift from facultative soft−bottom attachment to obligate hard−ground attachment in edrioasteroids involved the retention of a juvenile trait into adulthood and was already underway by the middle Cambrian.
4
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The youngest ctenocystoids from the Upper Ordovician of the United Kingdom and the evolution of the bilateral body plan in echinoderms

84%
Rahman I. A., Stewart S. E., Zamora S.
Acta Palaeontologica Polonica
|
2015
|
tom 60
|
nr 1
During the early Palaeozoic, echinoderm body plans were much more diverse than they are today, displaying four distinct types of symmetry. This included the bilateral ctenocystoids, which were long thought to be restricted to the Cambrian. Here, we describe a new species of ctenocystoid from the Upper Ordovician of Scotland (Conollia sporranoides sp. nov.). This allows us to revise the genus Conollia, which was previously based on a single poorly-known species from the Upper Ordovician of Wales (Conollia staffordi). Both these species are characterized by a unique morphology consisting of an elongate-ovoid body covered in spines, which clearly distinguishes them from their better-known Cambrian relatives; they are interpreted as infaunal or semi-infaunal burrowers from deep-water environments. This indicates that the ctenocystoid body plan was not fixed early in the evolution of the group, and they most likely modified their structure as an adaptation to a new mode of life in the Ordovician.
5
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The oldest representative of a modern deep-sea ophiacanthid brittle-star clade from Jurassic shallow-water coral reef sediments

84%
Thuy B., Schulz H.
Acta Palaeontologica Polonica
|
2013
|
tom 58
|
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.
6
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Aspects of life mode among Ordovician asteroids: Implications of new specimens from Baltica

84%
Blake D. B., Rozhnov S.
Acta Palaeontologica Polonica
|
2007
|
tom 52
|
nr 3
A new genus and species of Asteroidea (Echinodermata), Estoniaster maennili, is described from the Upper Ordovician (Caradocian) of Estonia; it is similar to the western European genus Platanaster and the North American Lanthanaster and an as yet unpublished new genus. Specimens of Urasterella? sp. and Cnemidactissp. are recognized from the Middle Ordovician of northwest Russia; although similar to known species, incomplete preservation precludes more precise taxonomic assessment. Asteroids are important in many existing marine communities, and in spite of a meager fossil record, diversity suggests they were important in the early Paleozoic as well. Some debate has centered on arm flexibility in early asteroids, which bears on their roles in their communities. Parallels in ambulacral series arrangement between Ordovician and extant species and presence of an ambulacral furrow indicate similar broad ranges of motion and therefore potentially parallel ecologic roles. Many factors might have contributed to the differences between ancient and extant ambulacral articulation, including changes in positioning of a part of the water vascular system, changes in predation and bioturbation pressures, and taphonomic events that obscure skeletal details.
7
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Stylophoran supertrees revisited

84%
Lefebvre B.
Acta Palaeontologica Polonica
|
2005
|
tom 50
|
nr 3
Supertree analysis is a recent exploratory method that involves the simultaneous combination of two or more character−based source trees into a single consensus supertree. This method was recently applied by Ruta to a fossil group of enigmatic Palaeozoic forms, the stylophoran echinoderms. Ruta’s supertree suggested that mitrates are polyphyletic and originated from paraphyletic cornutes. Re−examination of Ruta’s data matrix strongly suggests that most source trees were based on dubious homologies resulting from theory−laden assumptions (calcichordate model) or superficial similarities (ankyroid scenario). A new supertree analysis was performed using a slightly corrected version of Ruta’s original combined matrix; the 70% majority−rule consensus of 24,168 most parsimonious supertrees suggests that mitrates are monophyletic and derived from paraphyletic cornutes. A second new supertree analysis was generated to test the influence of the pruning of three taxa in some calcichordate source trees; the 70% majority−rule consensus of 3,720 shortest supertrees indicates that both cornutes and mitrates are monophyletic and derived from a Ceratocystis−like ancestor. The two new supertree analyses demonstrate the dramatic influence of the relative contributions of each initial assumption of plate homologies (and underlying anatomical interpretations), in original source trees, on the final topology of supertrees.
8
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A species-level supertree for stylophoran echinoderms

84%
Ruta M.
Acta Palaeontologica Polonica
|
2003
|
tom 48
|
nr 4
The construction of supertrees from smaller, character−based cladograms permits simultaneous inclusion of a large number of taxa in a single analysis, summarizes patterns of relationships from many independent data sources, and highlights areas of conflict to be targeted by character matrix studies. The method is applied for the first time to stylophoran echinoderms (cornutes and mitrates). Published cladistic analyses of this problematic group are used to build a supertree of 77 species. Key areas of stylophoran phylogeny to be addressed by future studies include the systematic placement of several mitrate−like cornutes, the affinities of peltocystidan and lagynocystid mitrates, and the position of such bizarre−looking taxa as Diamphidiocystis and Lobocarpus. A strict consensus of 72,278 equally parsimonious supertree solutions shows cornutes to be paraphyletic relative to mitrates. Lobocarpusis either one of the most derived cornutes or the sister taxon to all mitrates, in agreement with its chimaera−like combination of cornute− and mitrate−like features. Chinianocarpos is basal to peltocystidan rather than to mitrocystitidan mitrates. Nanocarpus, an almost bilaterally symmetrical taxon previously allied to cornutes, is nested within mitrates as sister taxon to mitrocystitids plus anomalocystitids. Diamphidiocystis and Lagynocystis cause loss of phylogenetic resolution among derived mitrocystitids and basal anomalocystitids.
9
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A new pleurocystitid blastozoan from the Middle Devonian of the Eifel (Germany) and its phylogenetic importance

67%
Nardin E., Bohaty J.
Acta Palaeontologica Polonica
|
2013
|
tom 58
|
nr 3
Rich echinoderm fauna from the Middle Devonian of the Eifel (Rhenish Massif, Germany) has yielded specimens of the rare recumbent pleurocystitid rhombiferans. Regulaecystis testudineus sp. nov. extends the stratigraphic range of the pleurocystitids to the Eifelian (Middle Devonian). Specimens show a strongly inflated and ornamented theca, which is unusual for the European pleurocystitids. Phylogenetic analysis of all described pleurocystitid genera suggests a close relationship of Regulaecystis with the other Devonian genera. Results indicate that the degree of inflation and of ornamentation of the theca can be interpreted as convergences within the pleurocystitids due to environmental conditions (such as surface consistency, hydrodynamism). R. testudineus sp. nov. was living as a strict epibenthic vagile organism; lying on muddy soft to firm substrates in quiet to agitated shallow warm water environments.
10
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Crinoids from the Silurian of Western Estonia

67%
Ausich W. I., Wilson M. A., Vinn O.
Acta Palaeontologica Polonica
|
2012
|
tom 57
|
nr 3
The Silurian crinoids of Estonia are re−evaluated based on new collections and museum holdings. Nineteen species−level crinoid taxa are now recognized. All crinoid names applied to Estonian Silurian crinoids during the middle 19th century are disregarded. Especially significant is the fauna reported herein from the Pridoli because coeval crinoids are very poorly known from the Baltic region and elsewhere. One new genus and four new species are described from Estonia, namely Calceocrinus balticensis sp. nov., Desmidocrinus laevigatus sp. nov., Eucalyptocrinites tumidus sp. nov., and Saaremaacrinus estoniensis gen. et sp. nov.
11
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Palaeoenvironmental control on distribution of crinoids in the Bathonian [Middle Jurassic] of England and France

67%
Hunter A. W., Underwood C. J.
Acta Palaeontologica Polonica
|
2009
|
tom 54
|
nr 1
77-98
Bulk sampling of a number of different marine and marginal marine lithofacies in the British Bathonian has allowed us to assess the palaeoenvironmental distribution of crinoids for the first time. Although remains are largely fragmentary, many species have been identified by comparison with articulated specimens from elsewhere, whilst the large and unbiased sample sizes allowed assessment of relative proportions of different taxa. Results indicate that distribution of crinoids well corresponds to particular facies. Ossicles of Chariocrinus and Balanocrinus dominate in deeper−water and lower−energy facies, with the former extending further into shallower−water facies than the latter. Isocrinus dominates in shallower water carbonate facies, accompanied by rarer comatulids, and was also present in the more marine parts of lagoons. Pentacrinitesremains are abundant in very high−energy oolite shoal lithofacies. The presence of millericrinids within one, partly allochthonous lithofacies suggests the presence of an otherwise unknown hard substrate from which they have been transported. These results are compared to crinoid assemblages from other Mesozoic localities, and it is evident that the same morphological adaptations are present within crinoids from similar lithofacies throughout the Jurassic and Early Cretaceous.
12
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A new brittle star from the early Carboniferous of Poland and its implications on Paleozoic modern-type ophiuroid systematics

67%
Thuy B., Kutscher M., Plachno B. J.
Acta Palaeontologica Polonica
|
2015
|
tom 60
|
nr 4
The fossil record of Paleozoic ophiuroids includes a number of forms which share striking similarities with modern relatives in terms of skeletal morphology. These so called modern-type Paleozoic ophiuroids yield an enormous potential for a better understanding of ophiuroid evolution, yet the scarcity of accurate and sufficiently detailed morphological descriptions available to date precludes any further-reaching assessments. Here, we describe an articulated ophiuroid specimen from the Late Tournaisian (early Carboniferous) of Czatkowice quarry, southern Poland, as a new species Aganaster jagiellonicus sp. nov. The good preservation of the specimen allowed for a morphological analysis at a level comparable to recent ophiuroid descriptions. It shows remarkable morphological similarities with extant former ophio-lepidids Ophiomusium and Ophiosphalma. The new find thus contributes to a solid basis for future investigations on the position of the modern-type Paleozoic ophiuroid in the phylogeny of the class.
13
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Nanostructural and geochemical features of the Jurassic isocrinid columnal ossicles

67%
Stolarski J., Gorzelak P., Mazur M., Marrocchi Y., Meibom A.
Acta Palaeontologica Polonica
|
2009
|
tom 54
|
nr 1
69-75
Calcite isocrinid ossicles from the Middle Jurassic (Bathonian) clays in Gnaszyn (central Poland) show perfectly preserved micro− and nanostructural details typical of diagenetically unaltered echinoderm skeleton. Stereom pores are filled with ferroan calcite cements that sealed off the skeleton from diagenetic fluids and prevented structural and geochemical alteration. In contrast with high−Mg calcite skeleton of modern, tropical echinoderms, the fossil crinoid ossicles from Gnaszyn contain only 5.0–5.3 mole% of MgCO₃. This low Mg content can be a result of either a low temperature environment (ca. 10℃) and/or low Mg/Ca seawater ratio. Both conditions have been proposed for the Middle Jurassic marine environment. Occurrence of Mg−enriched central region of stereom bars of Jurassic columnal ossicle of Chariocrinus andreae is consistent with the concept of magnesium ions involvement in earliest growth phases of calcium carbonate biominerals.
14
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Morphology and ontogeny of the Cambrian edrioasteroid echinoderm Cambraster cannati from western Gondwana

67%
Zamora S., Sumrall C. D., Vizcaino D.
Acta Palaeontologica Polonica
|
2013
|
tom 58
|
nr 3
A review of the Cambrian edrioasteroid echinoderm Cambraster cannati is made based on new collections from the Iberian Chains (NE Spain) and Montagne Noire (France). New morphological data include a completely articulated oral area and details of ambulacra. Specimens ranging from 4 to 26 mm in diameter provide detailed information concerning the full ontogeny. Important changes through ontogeny mainly affect the marginal ring and the plating pattern of the aboral surface. Comparison with other species of Cambrasterindicates that the aboral surface of Cambraster tastudorum from Australia shows strong resemblance to juvenile specimens of C. cannati. Cambraster cannati was attached directly to the substrate and inhabited relatively high energy, offshore environments from the west margin of Gondwana. Abnormalities in the skeleton are described for the first time in a Cambrian edrioasteroid.
15
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Middle Cambrian gogiid echinoderms from Northeast Spain: Taxonomy, palaeoecology, and palaeogeographic implications

67%
Zamora S., Gozalo R., Linan E.
Acta Palaeontologica Polonica
|
2009
|
tom 54
|
nr 2
253-265
Gogia parsleyi Zamora sp. nov. and Gogia sp. are described from two different echinoderm assemblages, both from the middle Cambrian of the Murero Formation (Iberian Chains, NE Spain). Gogia parsleyi is reconstructed and described on the basis of fifteen complete or partial specimens and numerous isolated plates. It is characterised by spiralled brachioles, simple epispires, sometimes covered by stereomic domes or tiny cover plates, and by thecal plates arranged in subregular circlets. This gogiid population comprises juveniles, advanced juveniles and mature individuals. The material was found in the upper part of the Murero Formation (upper Caesaraugustian–lower Languedocian). Gogia sp. is represented by two almost complete specimens and several isolated plates from the lower part of the Murero Formation (lower Caesaraugustian). The genus Gogia was first described in Western Gondwana from the Languedocian (upper middle Cambrian) of France, but the material from Spain is older and represents the oldest record of this genus in Gondwana, suggesting an early migration from Laurentia. The gogiids are well preserved in two echinoderm Lagerstätten, which, together with other echinoderms, comprise the majority of the fossil fauna. Both levels are derived from obrution deposits produced in calm and open marine conditions, sometimes affected by sporadic storms. Their holdfast morphology suggests that these gogiids were low−tier suspension feeders, living attached to trilobite fragments in a soft, muddy environment.
16

Reactions of Antarctic Sea urchins Sterechinus neumayeri [Echinodermata: Echinoidea] to glutamic acid and glucose

67%
Janecki T.
Polskie Archiwum Hydrobiologii
|
1999
|
tom 46
|
nr 3-4
17
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Symmetry disorders of the test of the Miocene echinoid Echinocyamus from Poland

67%
Ceranka T.
Acta Palaeontologica Polonica
|
2007
|
tom 52
|
nr 3
This paper presents cases of disorders in the test symmetry in three species of Echinocyamus (E. pusillus, E. calariensis, and E. apicatus) from the Miocene deposits of Poland. It is the first study of this topic based on fossil material. The large collection (ca. 60 000 specimens) allowed distinction of several types of these rare disorders (14 specimens), which are illustrated by SEM and explanatory drawings. An example of a deformity formed on the pentamerous system is also presented. The deformations develop in the rudiment; consequently the apical system and the test of the mature individual which is formed at its margin display disorders. The anomalies most commonly appear as an additional growth zone (6−ray symmetry), lack of one growth zone (4−ray symmetry), or both deformations simultaneously (changed 5−ray symmetry). The changes appear in the apical system (number of ocular pores), test (number of petals), and peristome outline. The anomaly linked with the incorrect position of the periproct on the test surface, resulting from the delay of its displacement during early ontogenic stages, is characteristic and unique for such deformations.
18
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A new Middle Cambrian stem-group echinoderm from Spain: Palaeobiological implications of a highly asymmetric cinctan

67%
Zamora S., Smith A. B.
Acta Palaeontologica Polonica
|
2008
|
tom 53
|
nr 2
A new exquisitely preserved stem group echinoderm (cinctan), Lignanicystis barriosensis gen. et sp. nov., is described from the Middle Cambrian of Los Barrios de Luna, North Spain. This displays a unique asymmetrical body plan with ventral projecting nodes that raised the lower surface above the substratum. There are four openings through the body wall: mouth, anus, atrium, and an aligned row of sutural pores of uncertain function. Unlike other cinctans, Lignanicystis has a strongly asymmetrical shape convergent with that of some cornute carpoids. Like cornutes, the test is also elevated above the substratum to allow water flow beneath the theca. In both cases this is probably an adaptation to life in higher water flow regimes.
19

Wczesna filogeneza zwierzat tkankowych w zapisie kopalnym

59%
Dzik J.
Kosmos
|
1996
|
tom 45
|
nr 4
657-686
20

Morski jez

59%
Adamska A., Adamski Z.
Wiedza i Życie
|
2002
|
nr 09
22-23
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