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Three species of Givetian and Frasnian trilobites have been recognized in the stromatoporoid-coral platform and Dyminy reef complex (Kowala Formation) of the southern part of the Holy Cross Mts, and two more in deeper facies of the Kostomłoty area. Representatives of the genus Scutellum, common in the shallow-water (related to carbonate buildups) associations of the Variscan Europe, are most widespread and diversified. Cyrtodechenella(?) declinans sp. n., Phacops (Chotecops) zofiae sp. n., and Scutellum mariae sp. n. are proposed.
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Devonian phoebodont shark teeth

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Shark teeth of the phoebodont type are the most common and diverse group of Upper Devonian ichthyoliths in the pelagic facies of the Holy Cross Mountains (Poland), South Urals and Timan (Russia). They were also found in the Givetian of Kuznetsk Basin (western Siberia). The morphology and function of tooth apparatus of Phoebodus was possibly similar to that of the recent shark Chlamydoselachus anguineus. A significant loss of diversity and relative productivity has been observed among the phoebodonts in the earliest Famennian. A new genus, Omalodus gen. n., and three new species of Phoebodus, Ph. bifurcatus sp. n., Ph. fastigatus sp. n. and Ph. turnerae sp. n. are proposed.
The Givetian and Frasnian strata of the Holy Cross Mountains, including chiefly biostromal sequence of the Kowala Formation, and the Dziewki Limestone of the Silesian Upland, yielded nine benthic and seven planktic tentaculite species. The tentaculites reveal strong affinities with coeval faunas of the East European Platform, and only two species from the oldest Givetian units (Stringocephalus-bearing strata), namely Homoctenus hanusi and Nowakia postotomari, are known primarily from the European Variscan belt. Stylioline succession allows recognition of the Middle/Late Devonian boundary in pelagic facies of the Kostomłoty area.
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Givetian and Frasnian crinoid faunas of the Holy Cross Mts and Silesia-Cracow Region are arranged in fourteen assemblages. Their diversity decreases generally from northern to southern regions reflecting crinoid habitat differentiation during either platform or reef phases of facies development. Distributional patterns are superimposed on a six-step general succession of the faunas which was mainly controlled by environmental changes related to eustatic cycles. Nine crinoid species have been identified by calyces, thirteen species are based on stems attributed to calyx genera, and forty-eight kinds of columnals, probably representing distinct species, are classified within artificial supraspecific units. Of them thirteen are new: Anthinocrinus brevicostatus sp. n., Asperocrinus brevispinosus sp. n., Calleocrinus bicostatus sp. n., Calleocrinus kielcensis sp. n., Exaesiodiscus compositus sp. n., Kasachstanocrinus tenuis sp. n., Laudonomphalus pinguicostatus sp. n., Noctuicrinus? varius sp. n., Ricebocrinus parvus sp. n., Schyschcatocrinus delicatus sp. n., Schyschcatocrinus multiformis sp. n., Stenocrinus raricostatus sp. n., and Urushicrinus perbellus sp. n.
Each developmental phase of the Givetian to Frasnian carbonate complex of the southern Holy Cross Mts is marked by distinctive calcareous microbiota. The Stringocephalus bank deposits contain a very rich, well-preserved microproblematica (of chiefly ?algal origin) dominated by calcispheroids, and many calcified cyanobacteria and green algae with filamentous Bevocastria, tubiform Devonoscale, and charophyte Trochiliscus. In the late Givetian biostromal complex more sparse microfossil associations occur, with the exception of locally abundant semitextulariid foraminifera (mainly Nanicella) and tubiform dasyclad(?) Jansaella. Also in the Frasnian back-reef facies, only limited and poorly preserved calcispheroids are identified. Contrarily, reef- and fore-reef microbiotas were present in great profusion. Microbial mats (including calcified cyanobacteria Renalcis and Sphaerocodium), associated with locally frequent solenoporids and multichambered foraminifera (Nanicella, also many nodosariids in the later Frasnian) played a significant depositional role and evidence progressive shoaling conditions within the Dyminy reef-complex.
Variable bioclastic-biostromal-marly Posłowice facies within the Late Givetian open-shelf Jaźwica Member in the SW part of the Holy Cross Mts contain palaeocopid-podocopid ostracod associations of moderate diversity (18 species) dominated by Microcheilinella fecunda and Fellerites tuimazensis. More deepwater and stagnant environments of the Bolechowice micrite-marly facies, supported similarly differentiated (12 species) but less equitable associations with platycopids Uchtovia rejrathensis and palaeocopids Buregia jazwicensis as a main component. Other late Givetian, and Frasnian reef and lagoonal microfaunas are mostly impoverished (at least in generic terms) and strongly predominated by podocopids, mostly Bairdiocypris. Late Givetian associations from the Kostomłoty basin are marked by the metacopid Polyzygia symmetrica, and the planktic entomozoid Ungerella torleyi Polenovula beckeri sp. n., Clavofabellina poslovicensis sp. n., Buregia jazwicensis sp. n., and Bairdia zbikowskae sp. n. are proposed.
Tabulate corals and single species each of the heliolitid anthozoans and chaetetid sclerosponges mostly from the Givetian and Frasnian stromatoporoid-coral series of the Holy Cross Mts and the Silesia-Cracow Region are reviewed from an ecological and stratigraphical point of view. Thamnopora, or the branched pachyporids, and massive alveolitids are usually the most significant reef-builders. The most distinctive fauna, with Caliapora battersbyi and Heliolites porosus, thrived in the earlier Givetian bank habitats. Late Givetian biostromal-complex associations with Alveolites obtortus, Striatopora enigmatica, and especially Alveolitella fecunda, as well as the succeeding Frasnian Alveolites-dominated reef-complex faunas with A. maillieuxi, and later with A. tenuissimus, Aulocystis and syringoporids, are far more uniform. In addition, a local Coenites laminosa-Chaetetes yunnanensis fauna is recognized in the Middle Givetian of the Kostomłoty area. The transitional biogeographic position for Polish tabulate assemblages between Variscan Europe and Russia is clearly evident. Forty eight species have been identified. Pachyfavosites polonicus sp. n., Striatopora enigmatica sp. n., Alveolitella polygona sp. n., Armalites minimus sp. n., and Syringoporella raritabulata sp. n., Alveolites edwardsi frasnianus subsp. n., and Caliapora battersbyi minor subsp. n. are proposed.
Givetian and Frasnian stromatoporoid-coral limestone of the Kowala Formation in the southern Holy Cross Mts is subdivided stratigraphically, and correlated with strata elsewhere on the basis of identified sea-level cyclicity, with support from conodonts and other selected benthic fossils. After the Eifelian hypersaline sabkha phase, an extensive two-step regional colonization of the Kielce Region carbonate platform took place during the Eifelian/Givetian passage interval and the Middle Givetian. At least four deepening pulses resulted in intermittent drowning of the vast carbonate platform and sequential replacement of the undifferentiated Stringocephalus biostromal bank by the Sitkówka bank complex and, subsequently, by the Dyminy reef complex. The reef developed in the central Dyminy belt as result of the early Frasnian accelerated sea-level rise after some period of biotic stagnation near the Givetian-Frasnian boundary. Final demise of the reef resulted from combined eustatic and tectonic movements during the late Frasnian major crisis interval.
Rugose corals of the Givetian to Lower Frasnian Kowala limestone Formation in the environs of Chęciny, SW Holy Cross Mts and in its age equivalents in the Silesian-Cracow region of Southern Poland represent five distinct assemblages of restricted time-and-space distribution. Within the Stringocephalus Beds the high diversity Pseudohexagonaria(?) laxa assemblage indicates open-shelf conditions whereas low diversity Temnophyllum occidentale assemblage represents restricted conditions. The transgressive Jaźwica Mbr. locally contains diversified and cosmopolitan Acanthophyllum sp. n. fauna. Following temporally coral assemblages, i.e. Disphyllum (lower Sitkówka and Chęciny Beds) and Macgeea-Thamnophyllum (Kadzielnia Mbr, upper Sitkówka Beds) are mostly biostromes of branching corals of low taxonomical diversity typical for restricted relatively setting, rather unfavorable for rugosans. Exceptional are two Hexagonaria horizons with common massive colonies. Diffiisolasma gen. nov., Sociophyllum severiacum sp. nov., Temnophyllum zamkowae sp. nov. and Hexagonaria hexagona kowalae subsp. nov. are proposed as the new taxa.
Disarticulated fish microremains from the Middle Givetian to early Frasnian of the Holy Cross Mts include representatives of the most groups known from the Devonian: placoderms, elasmobranchs, holocephalians, acanthodians, osteichthyans (mostly osteolepidids) and actinopterygians. Taxonomic identifications are possible usually only in very general terms and only in two cases the generic level has been reached: Phoebodus among euselachians, and Moythomasia among paleoniscids. Many of these groups, regarded traditionally as typical dwellers of lacustrine to resticted marine nearshore biotopes, apparently flourished also in the offshore, open shelf carbonate (peri-reefl settings. The sequential replacement of the fish faunas was primarily influenced by eustatic events, in like manner to invertebrate communities.
Calcareous octactinellid sponge spicules are abundant in the Givetian and early Frasnian organic buildups in the Holy Cross Mts and Siewierz anticline, Silesian Upland. Monaxone-bearing siliceous Demospongea (or ?lyssakid Hyalospongea) occupied coeval quiet-water basin habitats. Significant reorganization within these generally deeper-water associations occurred late in the Frasnian (a local rise of the lithistids associated with dictyids and lyssakids) and early in the Famennian (profusion of Hyalospongea).
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