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EN
The Lower Devonian of the Holy Cross Mountains is well-known in the field of vertebrate palaeontology but remains unrecognized as regards palaeoenvironmental reconstructions. We therefore analysed the spatial distribution and relative abundance of fossil vertebrates in this area within one time interval. The fauna from an Early Devonian (Emsian) siliciclastic bone-bearing breccia (the “Placoderm Sandstone”) exposed in four sections of the Łysogóry region and five sections of the Kielce region was analysed with respect to the frequency of the remains and their taxonomic affinity. The relative abundances of agnathans, acanthodians, placoderms, osteichthyans and chondrichthyans suggest more open marine conditions in the Łysogóry region and more terrestrial-influenced in the Kielce region during the Emsian. The results show that the average agnathan and acanthodian content of the Łysogóry region is significantly larger than that in the Kielce region. On the other hand, there are relatively fewer osteichthyans in the Łysogóry region and a significantly higher proportion of bony fishes was recorded in the fauna of the Kielce region. Placoderms are characterized by their generally similar frequency in both regions and from site to site in each of them, though a greater abundance was noted from the Kielce region. Likewise differences in the proportions of particular groups in the Kielce region suggest a large variety of marginal-marine environments under the influence of factors that might have included marine currents and variable conditions around a river mouth.
EN
The beginning of exploitation of the Lower Devonian sandstones on Barcza Hill, located in the Klonów Range in the central part of the Holy Cross Mountains, dates back to the first decade of the last century. Sandstones of the lower Emsian Barcza Beds, known in older literature as “placoderm sandstones” were mined here. By the time of World War II, there were seven mines that produced mainly paving stones and crushed stone. Three of them resumed work after the war: “Kopalnia Nowa”, “Byk” and “Przy Pomniku”. Unfavourable deposit conditions and competition of the neighbouring mining plants "Bukowa Góra” and "Wiśniówka” led to the abandonment of mining on Barcza Hill in the late 1950s. In 1984, the “Barcza” nature reserve was created, which included the two largest quarries: "Kopalnia Nowa”and "Byk”.
EN
Results of palynological studies of the Lower Devonian siliciclastic deposits of the Barcza Beds (Upper Pragian-Lower Emsian) from two abandoned quarries at Barcza in the Holy Cross Mts. is presented. Based on miospores, the biostratigraphic position of the tuffite horizon from the Barcza profile was defined as the early Emsian AB (annulatus-bellatulus) palynological Zone.
4
Content available Vascular structure of the earliest shark teeth
EN
Here we use synchrotron tomography to characterise dental vasculature in the oldest known tooth-bearing sharks, Leonodus carlsi Mader, 1986 and Celtiberina maderi Wang, 1993. Three dimensional reconstruction of the vascular system and microstructure of both taxa revealed a complex and dense network of canals, including horizontal, ascending and secondary bifurcated canals, as well as histological features consistent with an osteodont histotype. However, L. carlsi and C. maderi also exhibit significant morphological differences, showing Leonodus a typical diplodont tooth morphology with a linguo-labially elongated base, that contrast with Celtiberina’s teeth that show a single conical cusp curved lingually with a week developed flat base mesio-distally extended, perhaps reflecting distant relationship. These data are compatible with a pre-Devonian diversification of the two main tooth types traditionally recognised in Palaeozoic sharks (i.e., “cladodont” vs “diplodont”). Finally, our data demonstrate that existing dental classification schemes based on styles of vascularisation are over-simplified, especially when Palaeozoic taxa are considered.
EN
Placoid and polyodontode scales of stem chondrichthyans have been found in the early Lochkovian “Ditton Group” of the Brown Clee Hill district, Shropshire, England and at Talgarth, south Wales. One of the forms is assigned to a new species of Altholepis Karatajūtė-Talimaa, 1997, a genus already recognised from Lochkovian shallow marine deposits in Celtiberia, Spain and the Northwest Territories, Canada as well as the type locality in Podolia, Ukraine. Altholepis salopensis sp. nov. is based on small polyodontode scales with typically three to eight high odontodes; the scale form was previously considered to belong to acanthodian “Nostolepis” robusta (Brotzen, 1934). The structure of other scales formerly assigned to “Nostolepis” robusta has led us to erect a new genus Jolepis for this scale form, which differs from Altholepis in lacking an ordered layout of odontodes. Jolepis robusta (Brotzen, 1934), originally (and possibly still) considered to be an acanthodian, is also known from the Baltic countries, Russia, and northern Germany (ex erratic limestones). Scales of acanthodian Parexus recurvus Agassiz, 1845, and/or possibly from the stem chondrichthyan Seretolepis elegans Karatajūtė-Talimaa, 1968 (scales of these two taxa are barely distinguishable), and of stem chondrichthyan Polymerolepis whitei Karatajūtė-Talimaa, 1968 are also present. Altholepis, Jolepis gen. nov., Seretolepis Karatajūtė-Talimaa, 1968 and Polymerolepis KaratajūtėTalimaa, 1968 are found in marine deposits elsewhere; the British occurrence of these taxa adds to the debate on the sedimentological origins of the Lower Old Red Sandstone deposits in the Welsh Borderland. The geographic range of several early sharks is now known to extend around the Old Red Sandstone continent and beyond.
EN
The Lower Devonian ‘Placoderm Sandstone’ in the Holy Cross Mountains (HCM) is filled with abundant impressions of disarticulated vertebrate remains. The only acanthodian macroremains named to date are fin spines of Machaeracanthus polonicus Gürich. Fin spine impressions in slabs from the Winna Formation (Emsian) at Podłazie Hill (near Daleszyce) in the southern HCM, and also the Barcza Formation (?Lochkovian) at Barcza Quarry, Miedziana Góra Conglomerate (?Lochkovian), Gruchawka, and Zagórze Formation (middle–upper Emsian) at Bukowa Mountain in the northern HCM, reposited in the University of Warsaw, Polish Geological Institute-National Research Institute, Warsaw, and Natural History Museum, London collections, have been cast and studied in order to better document this poorly known taxon. As noted in other Machaeracanthus species, we have found that M. polonicus has two different morphotypes of spines, which abut lengthwise to form a pair of spines. Our investigations show that the fin spine assemblage includes Onchus overathensis as well as M. polonicus, and probably another undetermined acanthodian. The affinities of O. overathensis are reassessed. It is here considered to be a diplacanthiform, and reassigned to the genus Striacanthus, as S. overathensis. Acanthodian scapulocoracoids have also been identified, as well as tightly spiralled toothwhorls which could be from an acanthodian.
EN
The placoderm sandstone (Emsian, Holy Cross Mountains) exposed in the abandoned quarry at Podłazie Hill was revisited and excavated during fieldwork conducted in 2011-2013. Bone-bearing breccias were identified for the first time at this site and subjected to taphonomic analysis. Vertebrate remains are dominated by heterostracans, while true placoderms compose less than 20% of the total vertebrate assemblage. The high degree of fragmentation of the bones and low degree of abrasion indicate that the remains were reworked and transported before final burial. This is consistent with the mixed character of the bone accumulations, which comprise both open-shelf forms (acanthodians, chondrichthyans) as well as those related to marginal-marine environments (placoderms and sarcopterygians). The bone-bearing succession has been subdivided into five depositional facies attributed to a coastal lagoon influenced by stormy, possibly tidal conditions. The occurrence of the invertebrate trace fossil Ilmenichnus sp. accompanied by Lockeia and Monomorphichnus supports this interpretation.
EN
The Czarnolas and Zwoleń Formations of the Terebin IG 5 borehole, and the Terrigenous suite of the Giełczew PIG 5 borehole were analyzed for their spores. Palynological slides from a previous study of the Czarnolas Formation from the Pionki 4 borehole were re-examined and re-interpreted based on new observations and recent spore zonation publications. Two new cryptospores (Cymbohilates pusillus n. sp., Cymbohilates baculatus n. sp.) and two new trilete spores (Retusotriletes niger n. sp., Retusotriletes tuberiferus n. sp.) are described and illustrated. The Lower Devonian and probable Eifelian spore assemblages are assigned to Streelispora newportensis- Emphanisporites micrornatus (NM), Verrucosisporites polygonalis-Dibolisporites wetteldorfensis (PoW), Emphanisporites foveolatus-Verruciretusispora dubia (FD), and Acinosporites apiculatus-Calyptosporites proteus (AP) Oppel zones. These zones have been recognized in the Ardenne-Rhine regions. These data can also be compared to worldwide eustatic signatures. The spore data indicate that in the Radom-Lublin area marine sedimentation ended in either late early or early late Lochkovian, and the successive flooding commenced in late Emsian, probably the serotinus chron.
PL
Utwory dewońskie obszaru radomsko-lubelskiego występują w obrębie brzeżnej części platformy wschodnioeuropejskiej. Można tu wyróżnić wyraźne, ograniczone uskokami jednostki strukturalne, a to: wyniesiona część platformy (EPEEP), rów mazowiecko-lubelski (MLT) i wyniesienie radomsko-kraśnickie (RKU). Na ościennym terytorium Ukrainy przedłużenie wyniesionej części platformy zwane jest wyniesieniem północno-wołyńskim (NVU) i depresją południowo-wołyńską (SVD), a kontynucja rowu mazowiecko-lubelskiego nosi nazwę rowu lwowskiego (LT) (Fig. 1). Womawianym rejonie obecne są wszystkie trzy oddziały systemu dewońskiego leżące zgodnie na górnym sylurze. Ich podział biostratygraficzny jest wciąż niepełny, szczególnie jeśli chodzi o przybrzeżnomorskie i aluwialne osady nie zawierające diagnostycznej fauny. Celem niniejszej pracy jest przynajmniej częoeciowe wypełnienie tej luki. Przeprowadzone badanie palinologiczne dotyczyły formacji czarnoleskiej i zwoleńskiej z otworu Terebin IG 5 oraz serii terygenicznej z otworu Giełczew PIG 5 (Tabele 1, 2). Formacja czarnoleska i seria terygeniczna reprezentują osady przybrzeżnomorskie, zaś formacja zwoleńska osady aluwialne. Ponownie zbadano zespoły spor z formacji czarnoleskiej z otworu Pionki 4. Uzyskane przed 20 laty wyniki zostały w tej pracy reinterpretowane w oparciu o najnowsze obserwacje i nowsze publikacje dotyczące zonacji sporowej (Fig. 2). Zbadane zespoły były na ogół urozmaicone. Zawierały one zarówno kryptospory, jak i spory ze znakiem zrostowym (por. Figury 3–6). W interpretowaniu uzyskanych wyników badań posłużono się zonacją sporową stworzoną dla dewonu obszaru ardeńsko-reńskiego. Wyróżniono szereg zon Oppla oraz zon filogenetycznych lub interwałowych (Fig. 2). Górną część formacji czarnoleskiej (Terebin IG 5 i Pionki 4) zaliczono do zony Oppla Streelispora newportensis-Emphanisporites micrornatus (NM), zony filogenetycznej M (górna część dolnego lochkowu lub dolna część górnego lochkowu). Dolną część formacji zwoleńskiej (Terebin IG 5) zaliczono również do zony Oppla NM, zony ewolucyjnej Si (dolna częoeć górnego lochkowu). Górna częoeć formacji zwoleńskiej (Terebin IG 5) należy do zony Oppla Verrucosisporites polygonalis-Dibolisporites wetteldorfensis (PoW), zon interwałowych W i Su (prag, być może także najniższy ems). Seria terygeniczna (Giełczew PIG 5) należy do zon Oppla Emphanisporites foveolatus-Verruciretusispora dubia (FD) górnego emsu i Acinosporites apiculatus-Calyptosporites proteus (AP), obejmującej pogranicze ems/eifel. Uzyskane wyniki pozwalają na wysunięcie następujących stwierdzeń: 1. Górna część formacji czarnoleskiej (Pionki 4 i Terebin IG 5) reprezentuje ostatni etap sedymentacji morskiej, zakończonej w późnym wczesnym lochkowie (lub wczesnym późnym lochkowie). 2. Formacja zwoleńska (Terebin IG 5) zawiera utwory górnego lochkowu po prag lub najniższy ems. W tym rejonie brakuje znacznej części osadów emsu obecnych w rejonie Radomia (Pionki 1, 4, Ciepielów IG 1) 3. Seria terygeniczna (Giełczew PIG 5) należy do górnego emsu i (prawdopodobnie) dolnego eiflu. Początek sedymentacji morskiej w tym rejonie można datować pośrednio jako poziom konodontowy serotinus. Dolna granica tej serii odpowiada więc dolnej granicy formacji grzegorzowickiej i jej odpowiedników w Górach Świętokrzyskich. Zatem cykl transgresywnoregresywny II Narkiewicza et al. (1998) odpowiada cyklowi Ic Johnsona et al. (1985).
PL
Na podstawie wstępnej analizy oznaczeń fauny z "piaskowców plakodermowych" Güricha (1896) oraz Czarnockiego (1919) i porównaniem ich z nową kolekcją (nr OS-223) stwierdzono, że oznaczenie tejże fauny na poziomie rodzajów i gatunków, jest bardzo niepewne i może budzić kontrowersje. Nie mogąc jednak przebadać kolekcji Güricha i Czarnockiego (zaginęły w czasie wojny), autor po analizie swojego materiału potwierdził obecność prawie wszystkich wymienionych przez Güricha (1896) i Czarnockiego (1919) rzędów i rodzin ryb pancernych. Stwierdzono występowanie licznych przedstawicieli Arthrodira, a także odcisków płyt przedstawicieli rzędu Antiarcha, którego obecność w dewonie świętokrzyskim w ogóle, była wątpliwa.
EN
Preliminary analysis of descriptions of "Placoderm Sandstone "fauna by Giirich (1896) and Czarnocki (1919), and comparison with the author 's new collection (no. OS-223), revealed that identification of that fauna at the species level is dubious. It is unlikely to see the Giirich and Czarnocki 's collections (lost during the war time). Review of the newly collected material confirmed the presence of almost all the orders and families of placoderm fish listed by Giirich and Czarnocki. Especially important is the rediscovery of fragments ofantiarchs, as the whose presence of the order Antiarcha in the Devonian of the Holy Cross Mountains was doubted. Besides, the presence of the Arthrodira representatives is documented.
EN
The fragments of osteostracan exoskeleton from the Lover Devonian Severnaya Zemlya Formation of the Severnaya Zemlya archipelago, viz., Ungulaspis arctoa AFANASSIEVA & KARATAJUTE-TALIMAA, 1998 and Ateleaspis sp., were studied. The structure of the exoskeleton of non-tremataspid osteostracans was investigated by SEM for the first time. A reconstruction of the structure of the Ungulaspis arctoa exoskeleton is suggested. Because of the poorer preservation of the Ateleaspis sp., only preliminary observations on the thin structure of its exoskeleton could be made. The forms under investigation are characterized by a similar type of sculpture on the surface of the shied (small tubercles) and on the body scales (thin crests). Some similarities in the structure of their shield exoskeleton (the presence of distinctly expressed tesserae, the presence of radiating canals, the probable absence of perforated septa and pore fields) were indicated. Ungulaspis arctoa is remarkable in the possessing macromorphological features typical of both the Ateleaspis- and Scolenaspis-like osteostracans. This similarity in the structure of exoskeleton of the investigated forms provides additional evidence in support of the affinity of these groups of osteostracans and their possible origin from common ancestors.
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