(Třenice to Dobrotivá Formations) of the Barrandian, Bohemia
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Acta Musei Nationalis Pragae, Series B, Natural History, 58 (1–2): 1–82 issued October 2002 Sborník Národního muzea, Serie B, Přírodní vědy, 58 (1–2): 1–82 LINGULIFORMEAN AND CRANIIFORMEAN BRACHIOPODS OF THE ORDOVICIAN (TŘENICE TO DOBROTIVÁ FORMATIONS) OF THE BARRANDIAN,BOHEMIA MICHAL MERGL Department of Biology, University of West Bohemia, Klatovská 51, 306 19 Plzeň, Czech Republic Mergl, M. (2002): Linguliformean and craniiformean brachiopods of the Ordovician (Třenice to Dobrotivá Formations) of the Barrandian, Bohemia. – Acta Mus. Nat. Pragae, Ser. B, Hist. Nat., 58 (1–2): 1–82. Praha. ISSN 0036-5343 Abstract. A revision of linguliformean and craniiformean brachiopods of the Třenice, Mílina, Klabava, Šárka and Dobrotivá Formations confirms the presence of 61 species of the order Lingulida, twelve species of the order Acrotretida, ten species of Siphonotretida, four species of Paterinida and two species of Craniida. In total, 89 species have been recognized, 16 of them newly described and 15 determined only in generic level. Three new genera have been established: Mytoella, Wosekella, and Eoschizotreta. Three main community groups are recognized in the early Ordovician of the Barrandian having limited strati- graphical significance. The Obolus C. G. (Hyperobolus Community and westoniid communities) characterizes a transgres- sive, coarse siliciclastic base of the Ordovician, which was followed by the Leptembolon Community and the Acrotreta-elkaniid Community of the Acrotreta C. G. in the latest Tremadocian and the early Arenigian times. Both commu- nity groups were in the middle Arenigian followed by a new lingulate fauna of the Paterula assemblage in the deeper envi- ronment, but by mixed orthid-lingulate faunas in shallower environments. The Barrandian early Ordovician brachiopod fauna is closely related to the early Ordovician linguliformean brachiopod fauna of the Scandinavia and east European platform. This indicates a common interchange of the planctotrophic linguliformean brachiopods between the distant palaeocontinents, namely Baltica and North Gondwana in early Ordovician times. I Brachiopoda, Lingulata, Paterinata, Craniata, taxonomy, palaeoecology, Ordovician, Barrandian, Bohemia Received March 3, 2002 Introduction The systematic part describes or presents 87 linguli- formean species, some of them only at generic level. A few Organophosphatic brachiopods are, along with trilobites additional species including the species present in the stud- and orthid brachiopods, the most significant macrofossils in ied material and the giant obolid Thysanobolus giganteus the Lower and Middle Ordovician marine sediments. They (KOLIHA) have not been incorporated into the paper. This have been intensively studied in the last two decades. New ensues from rarity of material, less favourable preservation technical facilities, such as scanning electron microscope, and problems with the taxonomic placement. Nevertheless, microprobes, EDX and molecular studies make possible the other but rare finds often indicate a longer stratigraphical study of morphological details, shell structure and bio- range of particular taxon and despite their imperfect knowl- chemistry that is reflected in the new conception of the edge, the presented data may be significant for the brachio- organophosphatic brachiopod phylogeny. The new phyloge- pod phylogeny. Rare low-conical shells from the late ny introduced in Treatise on Invertebrate Paleontology, part Tremadocian sediments may be referred to craniiform bra- H, Brachiopoda (Williams et al. 1997, 2000) is accepted by chiopods, and thus represent their earliest known occur- the present author. However, many questions of the linguli- rence yet recorded. formean brachiopod phylogeny remain uncovered, and a systematic study will have to be inevitable done at some Historical overlook time. The Lower and Middle Ordovician sequence of the Bar- The first linguliformean brachiopods were described randian is remarkably rich in the organophosphatic bra- from the Barrandian area by Joachim Barrande in 1879. In chiopods. This was evident already since the pioneer work his earlier brachiopod work published in 1848 (Barrande of Joachim Barrande (1879) and the essential study of 1848) he noted the presence of Lingulella attenuata from Vladimír Havlíček (1982b). New methods and S.E.M. facil- quartzites of Quartzit-Etage (D) (= Letná Formation, ity uncovered high diversity and excellent preservation of Drabov Quartzites in current stratigraphy) but without any microbrachiopods also in the Barrandian. Their diversity detailed stratigraphical or locality data. and morphological disparity are comparable to the rich lin- Thirty years later, Barrande (1879) assigned 53 species gulate brachiopod faunas in terraines with the lime sedi- from the Ordovician period to the lingulate and crani- mentation in the Ordovician period (Baltic area, iformean brachiopods, 28 of them from the Třenice, Mílina, Kazakhstan, Laurentian platform) despite the almost exclu- Klabava, Šárka, and Dobrotivá Formations of current strati- sively siliciclastic sedimentation in the Barrandian during graphical sense. He established the new genus Paterula Ordovician time. BARRANDE, the remaining species were referred by him 1 to genera Lingula BRUGUIÈRE, Obolus EICHWALD and species Obolus barrandei (KLOUČEK) and noted its identi- Discina LAMARCK. He did not present species descrip- ty with Thysanotos siluricus (EICHWALD). He also noted tions or diagnoses and only fine lithographic drawings de- the presence of other small brachiopods, referred by him to fine the new species. Substantial part of his collection, the Obolus, Lingulella, Acrotreta, and Orbiculoidea, but without type specimens and other topotypic material currently are any other data. In his last paper, Koliha (1938) discussed the stored in the National Museum, Prague and are accessible stratigraphical significance of lingulate brachiopods for the for study. stratigraphy of Bohemia, and named, omitting the formal de- Some comments on the stratigraphic position of the early scription, a giant obolid Obolus giganteus n. sp. from the Ordovical linguliformean brachiopods were given by quarry “Na Chrástnici” in Břežany II. Jaroslav J. Jahn (1904). His field observations and critical The third author studying the Lower Ordovician bra- study of Barrande’s originals resulted in the compilation of chiopods between the World Wars was Robert Růžička. He the species list with valuable locality and stratigraphical data. described remarkable rich fauna from haematite lens dis- Between 1915 and 1925, Prof. Celda Klouček, an excel- covered in an abandoned iron ore mine near Holoubkov (V lent fossil collector of the early 20th century, presented sev- Ouzkém), including the lingulate and paterinate bra- eral papers about fossils from the Lower Ordovician of the chiopods. In his second work (1927) he determined twelve Barrandian. Apart from the faunal lists including bra- linguliformean brachiopods. Of these, he described newly chiopods from several localities (Klouček 1915, 1917a, the species Micromitra (Iphidella) Walcotti n. sp., Ku- 1917b, 1919, 1924a, 1925), he described the acrotretid torgina Kolihai n. sp., Siphonotreta Krafti n. sp., and Acrotreta minima var. grandis KLOU. n. sp. (Klouček Siphonotreta simulans n. sp. and presented the first formal 1919) from the Třenice Formation and Obolus complexus description of the species Acrotreta grandis KLOUČEK. var. punctatus, n. var., and Paterula ? prima n. sp. (Klouček His drawings are highly diagrammatic but descriptions and 1924a) from the Klabava Formation. Unfortunately, he did generic determinations are remarkably accurate. Other lin- not select any type specimens and presented only diagram- gulate brachiopods from the clayey shale of the Klabava matic drawings; therefore, his types cannot be recognized in Formation were studied between the wars by J. V. Želízko. his collection which is currently kept in the National Muse- In 1921, he described and well-illustrated six lingulate bra- um, Prague and the neotypes have been selected (Havlíček chiopods and defined Lingulella amygdala ŽEL. and Lin- 1980b, Mergl 1999b). The extensive Klouček’s collection gulella pusilla ŽEL. as new species. In 1943, Ferdinand has been used in the current study. Prantl described the unique find of a large siphonotretid In a preliminary work, Jan Koliha (1918) discussed dif- which he referred to the species Siphonotreta verrucosa ferences between the genera Lingula BRUGUIÈRE, Lin- (EICHWALD) known only from the Baltic area till that gulella SALTER, and Obolella BILLINGS, and described time. The specimens were found by G. Měska in a core of eleven species from the Lower Ordovician of the Barrandi- borehole in Krušná hora, in volcanoclastic sediments of the an, three of them as new [Obolus Kloučeki n. sp., Obolus upper part of the Klabava Formation. All the specimens of Nováki (KLOUČEK) n. sp., Lingulella libečovensis n. sp]. these authors are currently stored in the palaeontological He discussed the presence of genera Orbiculoidea collections of the National Museum, Prague. ORBIGNY and Acrotreta KUTORGA. Several varietes After the Second World War, the study of lingulate bra- [Obolus (Lingulobolus) Feistmanteli (BARR.) var. acicu- chiopods in the Barrandian ceased. In 1972, Vladimír tirostris n. var., O. (L.) Feistmanteli (BARR.) var. tenuil- Havlíček shortly described and illustrated the species Pty- amellosa n. var., Obolus (Westonia?) lamellosus (BARR.) chopeltis sp. n. from