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1
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Devonian bryozoans of the Holy Cross Mountains, Poland. Part 1. Ctenostomata

100%
Kiepura M.
Acta Palaeontologica Polonica
|
1965
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tom 10
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nr 1
Nine species and 3 subspecies of the Couvinian and Givetian bryozoans of the order Ctenostomata Busk, belonging to 5 genera: Ropalonaria Miller, Vinella Ulrich, Allonema Ulrich & Bassler, Ascodictyon Nicholson & Etheridge, Jr, and Eliasopora Bassler are described. Two of the described species have not been given names (Vinella sp. and Ascodictyon sp.), one is a new subspecies (Allonema moniliforme parvum n. subsp.) and five - new species (Ropalonaria givetiana n. sp., Ascodictyon sparsiforme n. sp., Ascodictyon vinelliforme n. sp., Ascodictyon venustum n. sp. and Eliasopora devoniana n. sp.). The specimens in vestigated come from the localities Skały and Grzegorzowice, situated in the eastern part of the Bodzentyn syncline. The problems of age, stratigraphic and geographical range, as well as ecological conditions of the Ctenostomata assemblage investigated are discussed.
2
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Morphogenetic gradients in graptolites and bryozoans

100%
Urbanek A.
Acta Palaeontologica Polonica
|
2004
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tom 49
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nr 4
Despite independent evolution of coloniality in hemichordates and bryozoans, their colonies show common features. In both instances colony is a genet or clonal system composed of zygotic oozooid and a number of blastozooids (= modules) integrated by physical continuity of tissues, sharing a common genotype and subject to common morphogenetic control. In some groups of graptolites and bryozoans, colonies display a regular morphological gradient. Simple graptoloid and bryozoan colonies consist of a proximal zone of astogenetic change and a distal zone of astogenetic repetition. Observed morphological gradient may be attributed to diffusion, along the colony axis, of a morphogen produced by the oozooid; in the zone of astogenetic change the morphogen is above certain threshold level and drops below it in the zone of astogenetic repetition. This model is supported by observations on regeneration of fractured graptoloid colonies. Regenerative branch never displays astogenetic change. The same rule is valid for regeneration of fractured bryozoan colonies. While the early astogeny of simple bryozoan colonies may be explained within the framework of the gradient theory, the late astogeny of more complex ones involves multiple succession of zones of change and repetition, without analogy in astogeny of graptoloids. Thus, late astogeny in bryozoan colonies may be controlled by cyclic somatic/reproductive changes, probably independent of the primary morphogen. Evolutionary changes in the graptoloid colonies involve both the spreading of the novelties over a greater number of zooids (penetrance) and an increase in the degree of phenotypic manifestation of a given character (expressivity). In the phylogeny of bilaterian colonies morphogenetic gradient probably originated as a sort of a side effect of sexual process leading to the appearance of the oozooid. The latter contaminated the neighbouring blastozooids with the products of its own morphogenesis. The resulting morphogenetic gradient could be used by selective forces to produce various effects of adaptive significance. Morphogens responsible for patterning of bilaterian colonies are probably related to the products of genes responsible for the anteroposterior control of embryos in all solitary Bilateria (Hox, zootype genes).
3
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Lower Permian bryozoans from southern and central Spitsbergen, Svalbard

80%
Nakrem H. A., Blazejowski B., Gazdzicki A.
Acta Palaeontologica Polonica
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2009
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tom 54
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nr 4
Bryozoans from the Lower Permian Treskelodden and Wordiekammen formations of southern and central Spitsbergen respectively, Svalbard, have been studied. Twenty species are identified, including one new genus, Toulapora gen. nov., with Toulapora svalbardense as type species and one new species, Ascopora birkenmajeri sp. nov. The taxonomic composition is typical Lower Permian, with species in common with Timan−Pechora and the Urals (Russia) and Ellesmere Island (the Canadian Arctic). Growth habits reflect a moderately to deeper shelf environment.
4
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Late Tortonian bryozoans from Mut Basin, Central Anatolian Plateau, southern Turkey

80%
Zagorsek K., Gordon D. P.
Acta Palaeontologica Polonica
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2013
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tom 58
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nr 3
Sixteen bryozoan species have been identified in the Başyayla section, Mut Basin, southern Turkey. Five of these species are described here, including two new to science representing new genera: Basyaylella elsae gen. et sp. nov. and Ostrovskia triforamina gen. et sp. nov. The other three described species (Exidmonea sp., Biflustra savartii, and Margaretta sp.) show unusual features that have not been reported previously. Based on bryozoan data, the Başyayla sequence represents a tropical to subtropical, normal marine environment, with seafloor composed of fine sedimentary particles in a low−energy setting.
5

Relationship between nematode community and biomass and composition of periphyton developing on artificial substrates in floodplain lake

80%
Vidakovic J., Palijan G., Cerba D.
Polish Journal of Ecology
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2011
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tom 59
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nr 3
Periphyton colonisation on artificial substrate (microscopic glass slides) was investigated from July to November 2007, in Lake Sakadaš (Danube River floodplain Kopački rit, Croatia). Two different stations were chosen due to different post – flood conditions. The aim of the study was to follow temporal changes of nematode community composition and trophic structure in relation to periphyton biomass and bacterial abundance. In bryozoan – dominated periphyton (Plumatella emarginata Allman, 1844) nematodes were represented by 86 and 87% of total associated invertebrate fauna at S1 and S2 respectively. Total nematode abundance (up to 600 ind. 10 cm-2 at one station and up to 1130 ind. 10 cm-2 at another station) correlated significantly with the abundance (meaured as CFUs – colony forming units) of copiotrophic and oligotrophic bacteria at one station (r = 0.963, 0.998, P <0.05) and with organic and inorganic content of periphyton at another station (r = 0.891, 0.899, P <0.05). Nematode trophic groups (epistrate feeders, chewers, detritus feeders and suction feeders) were equally developed at both stations except detritus feeders whose species richness and abundance were significantly higher at the S1. Epistrate feeders were the most abundant trophic group in nematode assemblages at both stations with Chromadorina bioculata being the dominant species. Change in dominance of epistrate feeders by chewers (Brevitobrilus stefanskii) and suction feeders (Crocodorylaimus sp.) coincided with the occurrence of flood pulse. Effect of flood pulse on nematode community structure was probably indirect, alterating concentration of dissolved oxygen which chromadorids are sensitive to. The structure of nematode community developed through time differs between investigated stations indicating high sensitivity to bacterial abundance, periphyton biomass and P. emarginata mats which made the habitat more diverse and patchy.
6
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Trepostome bryozoans encrusting Silurian gastropods: A taphonomic window and its implications for biodiversity

80%
Buttler C. J., Cherns L., McCobb L. M. E.
Acta Palaeontologica Polonica
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2022
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tom 67
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nr 3
7
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Exceptional soft-tissue preservation in boring ctenostome bryozoans and associated “fungal” borings from the Early Devonian of Podolia, Ukraine

80%
Olempska E.
Acta Palaeontologica Polonica
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2012
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tom 57
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nr 4
Colonies of boring ctenostome bryozoans and microborings of “fungi” that occur in the Early Devonian (Lochkovian, ~416 Ma) of Podolia, western Ukraine, have soft−tissue preserved by phosphatization. These comprise exceptional three−dimensional body walls of feeding zooids with probable parietal muscles inserted on the cystid wall, and setigerous collars twisted within the vestibulum. The presence of collars in this Early Devonian ctenostomes proves the existence of this feature for more than 416 Ma of ctenostome evolution. Phosphatized remains of the zooid walls are interpreted as relicts of the originally chitinous cystid walls. This is the first record of soft−tissue fossilization in a boring bryozoan. The presence of cavities (specialized heterozooids), empty or filled with laminated calcium phosphate, is also documented in bryozoans for the first time. These cavities are interpreted as “store−rooms” in which the bryozoans accumulated nutrients. The new taxon, Podoliapora doroshevi gen. et sp. nov. is described. In additional, phosphatised fungi−like endoliths co−occur with bryozoans.
8
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Late Carboniferous bryozoans from La Hermida, Spain

80%
Ernst A., Minwegen E.
Acta Palaeontologica Polonica
|
2006
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tom 51
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nr 3
Fifteen bryozoan species belonging to thirteen genera have been identified from an outcrop of the Picos de Europa Formation (Moscovian, Upper Carboniferous) at La Hermida in northern Spain. Three species and one genus are new— Coscinium hermidensissp. nov., Cystodictya pustulosa sp. nov., and Cystocladia hispanica gen. et sp. nov. Rhabdomesid bryozoans are the most diverse order with seven species, followed by cystoporids (four species), fenestellids (three species) and trepostomids (one species). Bryozoans with erect branched or reticulate colonies dominate in the studied assemblage; only two species possess encrusting colonies. Together with associated crinoids, the bryozoan assemblage indicates a subtidal environment below the zone of vigorous water movement. The La Hermida bryozoan fauna confirms the Upper Carboniferous age of the Picos de Europa Formation and allows various biogeographical interpretations. All previously known species of the genus Coscinium were reported from the Lower Permian of Russia. Clausotrypa monticola is known from the Lower Permian of Russia and Arctic as well as from the Upper Carboniferous of Carnic Alps (Austria). Rhabdomeson cf. propatulissimum and Penniretepora pseudotrilineata are known from the same level of Italian Carnic Alps. Streblotrypa (Streblascopora) nikiforovae and Rhombocladia punctata are known from the Upper Carboniferous (Moscovian) of Ukraine. Fistulipora petaloida is known from Kasimovian Stage of Russian Plate. Several other species show connections with North America.
9
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Middle Jurassic cyclostome bryozoans from the Polish Jura

71%
Zaton M., Taylor P. D.
Acta Palaeontologica Polonica
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2009
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tom 54
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nr 2
267-288
New collections of bryozoans from the Middle Jurassic (Late Bajocian and Bathonian) of Poland add significantly to our knowledge of the diversity and biogeography of the Cyclostomata at a time when they were the dominant bryozoan order in the fossil record. A total of 16 species and one form−genus (“Berenicea”) are present. Most are encrusters, predominantly on hiatus concretions. A single erect species was found in deposits interpreted as regurgitates of a marine vertebrate. The following new species are described: Microeciella annae sp. nov., M. kuklinskii sp. nov., M. maleckii sp. nov., M. mokrskoensis sp. nov., M. magnopora sp. nov., Reptomultisparsa harae sp. nov., and Hyporosopora bugajensis sp. nov. The taxonomic importance of the morphology of both the gonozooids and pseudopores is underlined, especially for encrusting species of the “Berenicea” type that are otherwise difficult to distinguish from one another. The described bryozoan assemblage encrusting hiatus concretions from the Polish Middle Jurassic is the richest that has been documented globally from this kind of substrate.
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