Oldřich Fatka

The ‘microcontinent’ Perunica: status and story 15 years after conception

Abstract Central Europe consists of a complex mosaic of more or less independent terranes with varying tectonometamorphic histories, usually also of different lithological compositions and protolith, and thus it is reasonable to suppose that the majority of these blocks have experienced somewhat different palaeogeographical evolution. The present terrane juxtaposition has been interpreted in general as a result of the Variscan collision of peri-Gondwanan and peri-Baltic derived terranes, with Gondwana on one side and Baltica and/or Laurentia on the other side. However, reconstruction of the pre-Variscan development and mutual palaeogeographical relationships remains a major challenge of interpretation.

Stratigraphical distribution of Cambrian fossils in the Příbram-Jince Basin (Barrandian area, Czech Republic)

The stratigraphical distribution of all the fossil taxa known from the Cambrian Příbram-Jince Basin of the Barrandian area are shown in seven tables. Crustaceans, trace fossils, macroscopical algae, and microfossil taxa have been established in the Lower Cambrian Paseky Shale Member (Holšiny-Hořice Formation). Ranges of molluscs, brachiopods, echinoderms, miomerid and polymerid trilobites, crustaceans, trace fossils, incertae sedis, foraminifers, and acritarchs have been plotted on biostratigraphical charts of the Middle Cambrian Jince Formation.KurzfassungDie stratigraphische Verbreitung aller fossilen Taxa des Příbram-Jince-Beckens (Barrandium) sind in sieben Tabellen dokumentiert. Krustentiere (Crustacea), Spurenfossilien, makroskopische Algen und Mikrofossilien sind aus dem unterkambrischen Paseky-Schiefer (Holšiny-Hořice-Formation) bekannt. Die stratigraphischen Reichweiten der Mollusken, Brachiopoden, Echinodermen, miomeride und polymeride Trilobiten, Krustentiere, Spurenfossilien, Incertae sedis, Foraminiferen und Acritarchen sind in biostratigraphischen Tabellen der Jince-Formation (Mittleres Kambrium) aufgezeigtResumenSe presenta en 7 tablas la distribución de todas los taxones fósiles conocidas en el Cámbrico de la cuenca de Příbram-Jince (region «Barrandian»). En el Miembre Pisanas de Paseky (Formación Holšiny-Hořice, Cámbrico inferior) se localizan estratigraficamente una sociación fosil compuesta por crustáceos, pistas fósiles, algasmacroscópicas y microfósiles. En las tables de la Formación Jince (Cámbrico medio) se sitian los ranges estratigraficas de moluscos, braquiópodes, equinodermos, trilobites (agnóstidos, polímeros), crustáceos, icnofósiles, foraminiferos, acritarcos y problematica.

Paleoecologic Implications of Ichnofossils Associated with Slightly Skeletonized Body Fossils, Middle Cambrian of the Barrandian Area, Czech Republic

Several sites of the Middle Cambrian Jince and Buchava formations (Barrandian area, Czech Republic), showing features of Burgess Shale-type preservation, yielded diverse ichnofossils adjacent to non- or poorly biomineralized body fossils of arthropods, and less commonly, acrotretid brachiopods. Based on morphology, Gordia-like, Cochlichnus-like, Planolites-like, Treptichnus-like and Pilichnus-like traces occur with “nondescript” bioturbation. Ethologically, the Gordia-like and Cochlichnus-like traces are interpreted as single-use traces of feeding on microbial halo. Treptichnus-like and Pilichnus-like traces suggest later feeding systems associated also with feeding on microbial halo, and Planolites-like traces likely represent a fortuitous feature.

Shallow-Water Occurrence of Wiwaxia in the Middle Cambrian of the Barrandian Area, Czech Republic

Isolated sclerites of the genus Wiwaxia are reported from shale interlayers in lower levels of middle Cambrian (unnamed 3rd Series of Cambrian) Buchava Formation in the Skryje-Týřovice Basin in the Czech Republic interpreted as shallow-water sediments. Geographic distribution of Wiwaxia indicates latitudinal control as all occurrences are obviously restricted to tropical belt.

Lower Cambrian tubular micro-to macrofossils from the Paseky Shale of the Barrandian area (Czech Republic)

KurzfassungDas kohlig erhaltene Makrofossil (Megaalge)Marpolia spissaWalcott 1919 wird erstmals aus dem Frühkambrium des Barrandiums beschrieben. Makroskopische Koloniereste vonM. spissa werden mit tubulären Mikrofossilien aus denselben Gesteinen verglichen. Kolonien vonM. spissa enthalten verschiedene Bereiche, die mehreren (part-based) Mikrofossil-Gattungen und -Arten zugeordnet werden können. Die MikrofossilienSiphonophycus robustum (Schopf 1968)Knoll et al. 1991,S. typicum (Hermann 1974)Butterfield 1994, 5.kestronSchopf 1968,S. capitaneumNyberg &Schopf 1984,Polytrichoides lineatusHermann 1974, emend.Knoll et al. 1991,Tortunema angusta (Kolosov 1984)Butterfield 1994 undTortunema wernadskii (Schepeleva 1960)Butterfield 1994 sollten daher nur als Form-Spezies im Sinne einer künstlichen Taxonomie verwendet werden. Die Ablagerungsbedingungen des Paseky-Schiefers und die biologische Zugehörgkeit vonMarpolia spissa werden diskutiert.AbstractThe carbonaceous megafossil (mega-alga)Marpolia spissaWalcott 1919 is described from the Early Cambrian of the Barrandian area for the first time. Macroscopic remains of colonies ofM. spissa are compared with tubular microfossils of the same rocks. Different areas in colonies ofM. spissa are assignable to several (part-based) genera and species of microfossils. Therefore, the microfossil taxaSiphonophycus robustum (Schopf 1968)Knoll et al. 1991,S. typicum (Hermann 1974)Butterfield 1994,S. kestronSchopf 1968,S. capitaneumNyberg &Schopf 1984,Polytrichoides lineatusHermann 1974, emend.Knoll et al. 1991,Tortunema angusta (Kolosov 1984)Butterfield 1994 andTortunema wernadskii (Schepeleva 1960)Butterfield 1994 should only be used as form-species in the sense of an artificial taxonomy. The palaeoenvironment of the Paseky Shale and the biological assignment ofMarpolia spissa are discussed.

Gracilitheca and Nephrotheca (Hyolitha, Orthothecida) in the Cambrian of the Barrandian area, Czech Republic

VALENT, M., FATKA, O. & MAREK, L., iFirst article. Gracilitheca and Nephrotheca (Hyolitha, Orthothecida) in the Cambrian of the Barrandian area, Czech Republic. Alcheringa, 1–10. ISSN 0311-5518. Five orthothecid hyoliths, Gracilitheca mirabilis sp. nov., Gracilitheca triangularis sp. nov., Gracilitheca sp., Nephrotheca betula sp. nov. and Nephrotheca sp. are described from the ‘middle’ Cambrian Buchava Formation of the Skryje–Týřovice Basin in the Czech Republic. The new forms are based on about forty well-preserved external and internal moulds of conchs; opercula of all species remain unknown. Stratigraphic ranges and geographic distributions within the Skryje Týřovice Basin are established for all taxa.

The ontogeny of Ellipsocephalus (Trilobita) and systematic position of Ellipsocephalidae

Laibl, L., Fatka, O., Budil, P., Ahlberg, P., Szabad, M., Vokáč, V. & Kozák, V., 24.3.2015. The ontogeny of Ellipsocephalus (Trilobita) and systematic position of Ellipsocephalidae. Alcheringa 39, 477–487. ISSN 0311-5518. Well-preserved early holaspid stages of the Cambrian Series 3 trilobites Ellipsocephalus hoffi (Schlotheim, 1823) and Ellipsocephalus polytomus Linnarsson, 1877 have been discovered in the Příbram-Jince Basin (Czech Republic) and Jämtland (Sweden), respectively. Both species show remarkable morphological changes during late ontogeny. The earliest holaspides share long genal spines, and long macrospines on the second thoracic segment. Whereas macrospines disappear abruptly in later stages, genal spines are progressively shortened. Consequently, the ontogeny of trilobites of Ellipsocephalidae is revised. The morphology of early meraspid cranidia and ontogenetic patterns in the disappearance of macrospines suggest that this family is closely related to members of Redlichiida rather than Ptychopariida. Lukáš Laibl [lukaslaibl@gmail.com] and Oldřich Fatka [fatka@natur.cuni.cz], Charles University, Institute of Geology and Palaeontology, Albertov 6, 128 43, Prague 2, Czech Republic; Petr Budil [petr.budil@geology.cz], Czech Geological Survey, Klárov 3, Prague 1, 118 21, Czech Republic; Per Ahlberg [per.ahlberg@geol.lu.se], Department of Geology, Lund University, Sölvegatan 12, SE-223 62 Lund, Sweden; Michal Szabad [geosz.pb@seznam.cz], Obránců míru 75, 261 02 Příbram VII, Czech Republic; Václav Vokáč [lichas@seznam.cz], Ke Kukačce 21, 312 00 Pilsen, Czech Republic; Vladislav Kozák [vlada.kozak@tiscali.cz], K Moravině 11/1689, 190 00 Prague 9, Czech Republic.

Slapylitidae: a new family of hyolithids (Cambrian–?Devonian; Baltica, Laurentia, Gondwana)

Hyoliths are usually preserved as isolated skeletal elements consisting of conch, operculum, and helens. The occurrence of a conch associated with an operculum is ordinarily exceptional, and the co-occurrence of helens with other skeletal parts is a great rarity. The extraordinary finds of hyolithid conchs associated with opercula in situ are relatively abundant in the Cambrian and Ordovician clastic sediments of the Barrandian area in the Czech Republic. The platyclaviculate operculum with clavicles divided by longitudinal walls into channels characterizes members of the newly established family Slapylitidae fam. nov., which includes two genera: Slapylites Marek, 1980 known from the mid-Cambrian of West Gondwana and Baltica and Nevadalites Marek, 1976 documented from the Late Cambrian of Laurentia. To this family most probably belongs also an operculum from the Cambrian Series 2–Series 3 boundary of North Greenland and poorly known material from the Middle Devonian of Bolivia.KurzfassungHyolithen sind für gewöhnlich als isolierte skelettartige Elemente – bestehend aus Schale, Operculum und Helenen – erhalten. Das Auftreten einer Schale mit assoziiertem Operculum ist relativ ungewöhnlich und ein gleichzeitiges Vorkommen von Helenen mit anderen Skelettelementen zählt zu den großen Raritäten. Die ungewöhnlichen Funde von hyolithiden Schalen mit in situ erhaltenem Operculum sind vergleichsweise häufig in klastischen Sedimenten (Kambrium und Ordovizium) des Barrandiums der Tschechischen Republik zu finden. Das platyclaviculate Operculum mit Claviceln, durch längsgerichtete Scheidewände in Kanäle getrennt, charakterisiert Vertreter der neuen Familie Slapylitidae fam. nov., welche Vertreter zweier Gattungen beinhaltet: Slapylites Marek, 1980 (bekannt aus dem mittleren Kambrium West-Gondwanas und Balticas) und Nevadalites Marek, 1976 (belegt aus dem späten Kambrium von Laurentia). Dieser Familie gehört höchstwahrscheinlich auch das kaum bekannte Material aus dem Mittel-Devon Boliviens, wie auch ein Operculum aus dem Kambrium (Serie 2/Serie3-Grenzbereich) Nord-Grönlands, an.

Ichnogenus Astropolichnus in the Middle Cambrian of the Barrandian area, Czech Republic

ABSTRACT Imperfectly preserved specimen of a supposed hydrozoan Medusites cf. radiatus Linnars., originally described by Pompeckj (1896) from the “Pod trním” locality near Týřovice (Slapnice Member of the Buchava Formation, Skryje–Týřovice Basin) is revised. Recent study of the original specimen and a more complete topotype specimen testify the affiliation to the pineapple-shaped ichnogenus Astropolichnus Crimes and Anderson, 1985. A new ichnospecies A. bohemicus is established on the material from the Buchava Formation. This material is the first occurrence of Astropolichnus in the middle Cambrian as well as the first report of this ichnogenus in the Barrandian area of Czech Republic.

Skryjelites auritus gen. et sp. nov. and Quasimolites quasimodo gen. et sp. nov.--two new middle Cambrian hyolithids (?Mollusca) from the Czech Republic.

Two new endemic genera and species of extinct group of Hyolitha, Skryjelites auritus gen. et sp. nov. and Quasimolites quasimodo gen. et sp. nov. are described and illustrated from the Buchava Formation of the Barrandian area (Czech Republic).