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1
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Acritarchs from the Upper Ordovician of Southern Holy Cross Mountains, Poland

100%
Kremer B.
Acta Palaeontologica Polonica
|
2001
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tom 46
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nr 4
Acritarchs and prasinophyceans belonging to eleven genera have been found in the Upper Ordovician (Ashgill) deposits from Zalesie Nowe (Holy Cross Mountains, southern Poland). They are the first representatives of organic-walled plankton described thus far from the uppermost Ordovician/lowermost Silurian strata in the southern part of the Holy Cross Mountains.
2
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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
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tom 60
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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.
3
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Upper Ordovician brachiopods from Poland and Britain

67%
Temple J. T.
Acta Palaeontologica Polonica
|
1965
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tom 10
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nr 3
The brachiopods of the Upper Ordovician Hirnantia fauna from the Holy Cross Mountains of Poland (Góry Świętokrzyskie) are described. The fauna, which includes one new genus (Plectothyrella) and four new species (Philhedra? stawyensis, Hirnantia? kielanae, Platymena? polonica, Plectothyrella platystrophoides), is compared with occurrences from North Wales and the English Lake District.
4
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A low diversity shallow water lingulid brachiopod-gastropod association from the Upper Ordovician of Kyrgyz Range

67%
Popov L. E., Ebbestad J. O. R., Mambetov A., Apayarov F. K.
Acta Palaeontologica Polonica
|
2007
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tom 52
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nr 1
A low diversity association made up of the lingulid Tunisiglossa almalensis Popov and Mambetov, sp. nov. and the gastropod Ptychonema agyris Ebbestad, sp. nov. is described from the Upper Member of the Almaly Formation at Kyrgyz Range, North Tien Shan, Kyrgyzstan/Kazakhstan. The specimens co−occur in dense coquinas, made up of different sized individuals, deposited in a shallow water, intertidal, and storm driven depositional environment. The lingulid shells display a completely reduced dorsal pseudointerarea typical of Glossellinae, and the smooth shell lacking fine external granulation, radial or pitted ornament, a small ventral pseudointerarea, and no dorsal median ridge place it in the hitherto monotypic Tunisiglossa known previously only from the Lower Ordovician (Tremadocian) Sanrhar Formation of Libya. It compares with Ectenoglossa sorbulakensis that is widespread in the lower to middle Caradocian Anderken Formation of Chu−Ili Range in southern Kazakhstan. Gastropods of this age have not been reported earlier in Kyrgyzstan; neither can Ptychonema be compare with any taxon in the gastropod association earlier described from the contemporary Anderken Formation in Kazakhstan. Ptychonema is otherwise commonly associated with peri−Gondwana terranes, but the Late Ordovician dispersal pattern of the genus is unknown. Overall, however, the Upper Ordovician faunas of North Tien Shan show close similarities to contemporaneous faunas of the Chu−Ili terrane, which have strong biogeographic signatures linking them to the faunas of South and North China.
5
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The earliest known Kinnella, an orthide brachiopod from the Upper Ordovician of Manitoulin Island, Ontario, Canada

67%
Stott C. A., Jin J.
Acta Palaeontologica Polonica
|
2007
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tom 52
|
nr 3
A new species of the orthide brachiopod genus Kinnella is described from the Upper Member of the Georgian Bay Formation (Upper Ordovician) of Manitoulin Island, Ontario, Canada. This species, herein designated as Kinnella laurentiana sp. nov., occurs in strata of Richmondian (mid−Ashgill; Katian) age, most likely correlative with the eastern North American Dicellograptus complanatus Zone. This occurrence extends the known stratigraphic range of Kinnella downward considerably from its previously inferred basal Hirnantian inception. The new species is characterized by a moderately convex dorsal valve and an apsacline ventral interarea rarely approaching catacline. This is the third reported occurrence of Kinnella in North America, and is the only species known to have inhabited the epicontinental seas of Laurentia. The associated benthic shelly fauna indicates a depositional environment within fair weather wave base (BA 2). The ancestry of Kinnella and this species appears most likely to lie among older, morphologically similar members of the Draboviidae which were seemingly confined to higher latitude faunal provinces prior to the Hirnantian glacial event. Thus, the mid−Ashgill occurrence of Kinnella laurentiana in the palaeotropically located Manitoulin Island region suggests the mixing of a probable cooler water taxon with the warmer water epicontinental shelly fauna of Laurentia, as well as a possible earlier episode of low−latitude oceanic cooling. Cluster analysis of Kinnella−bearing brachiopod faunas reveals a sharp differentiation between the K. laurentiana−associated brachiopod fauna and all other known (Hirnantian–lower Rhuddanian) occurrences mainly represented by the type species K. kielanae.
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Pyritized tube feet in a protasterid ophiuroid from the Upper Ordovician of Kentucky, U.S.A.

67%
Glass A.
Acta Palaeontologica Polonica
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2006
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tom 51
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nr 1
A single specimen of the protasterid ophiuroid Protasterina flexuosa from the Kope Formation (Cincinnatian, Upper Ordovician) of Kentucky exhibits three−dimensionally pyritized tube feet. This represents the first report of soft−tissue preservation in an echinoderm from the type−Cincinnatian series. The tube feet are solid and lack all internal structure. They consist of aggregated masses of small euhedral to subhedral pyrite crystals suggesting that pyritization, although decay−induced and mediated, did not necessarily replicate soft−tissues but might instead have formed inside the void−spaces left behind during the decay process. The discovery of pyritized soft−tissue as delicate as ophiuroid tube feet suggests that similar forms of soft−tissue preservation might be found in other taxa in the Kope Formation. Perhaps much more importantly, this unexpected occurrence demonstrates the incompleteness of our knowledge of permissible conditions for the preservation of soft−tissues and it thereby indicates promise for discovery of other such occurrences in diverse organisms in unexpected settings. Systematics of Paleozoic ophiuroids remains problematic in spite of many years of study by capable paleontologists. The incomplete but well−preserved specimens treated here include the types of Protasterina flexuosa and Protasterina fimbriata as well as previously undescribed specimens. Together they permit a revised diagnosis and detailed description of the genus Protasterina. Protasterina fimbriata is the type species of the genus but is a subjective junior synonym of Protaster flexuosus (= Protasterina flexuosa). The genus is clearly differentiated from the only other known protasterid ophiuroid from the Cincinnatian series, Taeniaster spinosus, and from all other protasterid genera.
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