Bryozoan fauna from the Koněprusy Limestone (Pragian, Lower Devonian) of Zlatý Kůň near Koněprusy (Czech Republic)

Abstract

This paper presents an overview of the bryozoan fauna from the upper Koněprusy Limestone (kindlei Conodont Zone, middle Pragian, Lower Devonian) exposed in two quarries at Zlatý Kuň near Koněprusy in Central Bohemia, and discusses its paleoecology and paleobiogeography. The studied fauna is dominated by encrusting fistuliporine and trepostome bryozoans (eight species), accompanied mainly by reticulate fenestrates (four species), branching ramose trepostomes and cryptostomes (three species), and one massive trepostome species. The richest bryozoan association comes from reef core/margin facies (13 species), followed by crinoid-bryozoan facies of the ramp (eight species). The reef-terrace facies and the crinoid-bryozoan-algal facies contain three and two species respectively. Seven species are described taxonomically, three fistuliporines and four trepostomes. The following taxa are new: Koneprusiella armata n. gen. n. sp., Fistulipora rarivesiculata n. sp., Fistulipora hladili n. sp. and Leptotrypa varia n. sp. Paleobiogeographic patterns of the bryozoan fauna from the Koněprusy Limestone are similar to those of stromatoporoids, comprising widely distributed genera but mainly endemic species. This supports a relative geographic isolation of the Koněprusy reef. The bryozoan fauna from the Koněprusy Limestone shows paleogeographic affinities with that from the Lower Devonian (Pragian) of Morocco and the Middle Devonian of Michigan (USA).

Post-tectonic limitations on Early Devonian (Emsian) reef development in the Gobi-Altai region, Mongolia

“…The well‐preserved, whole and unabraded fossils of stenohaline organisms (brachiopods, stromatoporoids, corals, bryozoans and crinoids), coated grains and skeletal fragments micritized by endolithic borers, lack of deep‐water biotas, such as abundant cephalopods (Lubeseder 2008) and siliceous sponge spicules (Pohler 1998), and the continuous, gradational transition from the underlying subaerial–nearshore deposits of the Tsakhir Formation suggest that the palaeoenvironment was a shallow‐marine ramp. The abundance of lime mud, stromatoporoids and corals in growth position, complete solitary rugose corals, bryozoans comprising long, thin branches, and the occurrence, albeit rare, of intact crinoid columnals indicate that the environment was calm (Williams 1980; Zhen 1996; Ernst & May 2009). No wave ripples, interbedded siliciclastics, or intertidal indicators are evident, but variable wave energy is suggested by the high abundance of small skeletal fragments and the rare occurrence of overturned coral heads in some beds (Fig.…”

A bryozoan fauna from the Santa Lucia Formation (Lower–Middle Devonian) of Cantabrian Mountains, NW Spain

“…The genus Microcampylus is known from the Traverse Group (Middle Devonian, Eifelian) of Michigan, USA, from the Early Devonian (Pragian) of Bohemia (Ernst 2008b), and from the Middle Devonian of the Rhenish Massif (Ernst 2008a). Fistuliphragma gracilis Ernst 2008a is known from the Middle Devonian of the Rhenish Massif.…”

Petaloporella (Cryptostomata, Bryozoa) from the Lower Devonian of central Bohemia

“…Indeed, bryozoans can be reliable indicators of environmental conditions and useful for palaeobiographic analysis. The finding of Petaloporella bohemica and another rhabdomesine cryptostome species, Paracuneatopora striata Ernst, 2008, in the Lower Devonian of Morocco (Bigey 1994) suggests a close relationship between these two areas. However, Pragian and Emsian bryozoan communities of Spain rarely contain Bohemian species (unpublished data).…”

“…The material for the present study comes from the upper Koněprusy Limestone, sampled from two quarries ("Čer-tovy schody") in the vicinity of Zlatý Kůň Hill which lies 1 km south of the Bohemian village of Koněprusy (ca 30 km south-west of Prague, the Czech Republic; see Ernst & May 2009). The upper Koněprusy Limestone is middle Pragian in age and can be assigned to the kindlei Conodont Zone (Slavík 1998, May 2005 in the standard conodont zonation or to the serratus Conodont Zone in the alternative conodont zonation of Slavík (2004).…”

“…The study of bryozoans began in the 19 th century, and up until now, 76 bryozoan species have been recorded from the Pragian to Emsian sequence of central Bohemia (see an overview in Ernst 2008 andErnst &May 2009). A few recent publications provide taxonomic descriptions of the bryozoan fauna from the Koněprusy Limestone (Pragian, Lower Devonian) of Zlatý Kůň near Koněprusy, the Czech Republic (McKinney & Kříž 1986, Ernst 2008, Ernst & May 2009). Prantl (1935) described several bryozoan taxa including a new genus, Petaloporella, from the Lower Devonian Braník Limestone (Zlíchovian = Lower Emsian) of Braník, the Czech Republic.…”