New information on acritarchs from the Duolbagáisá Formation, Digermulen Peninsula, Arctic Norway, enable recognition of the three Cambrian Series 2 acritarch-based zones: the Skiagia ornata–Fimbriaglomerella membranacea, Heliosphaeridium dissimilare–Skiagia ciliosa and Volkovia dentifera–Liepaina plana Assemblage zones. Acritarchs of the Skiagia ornata–Fimbriaglomerella membranacea Zone (Cambrian Stage 3) appear near the base of the unit, close to an undetermined trilobite. In the Upper Member of the Duolbagáisá Formation, in levels with Kjerulfia n. sp. and Elliptocephala n. sp., appears an assemblage with abundant Skiagia ciliosa, indicative of the Heliosphaeridium dissimilare–Skiagia ciliosa Zone. A few metres higher appear Liepaina plana, Heliosphaeridium notatum and Retisphaeridium dichamerum, which indicate the Volkovia dentifera–Liepaina plana Zone (Cambrian Stage 4). The transition between the Duolbagáisá Formation and the overlying Kistedalen Formation is marked by the appearance of Comasphaeridium longispinosum, Multiplicisphaeridium llynense and Eliasum llaniscum, diagnostic of the Miaolingian Series. This coincides with the disappearance of Skiagia; occurrences of Skiagia in Miaolingian strata consist of reworked material related to the Hawke Bay regression at the Cambrian Stage 4–Wuliuan transition. The absence of Skiagia in higher levels of the Duolbagáisá Formation and Kistedalen Formation suggests that no unconformity formed during the Hawke Bay regression in this area. The chronostratigraphical significance of the Skiagia ornata–Fimbriaglomerella membranacea, Heliosphaeridium dissimilare–Skiagia ciliosa and Volkovia dentifera–Liepaina plana zones is critically analysed. Correlation of the Duolbagáisá Formation with peri-Gondwanan terrains of Avalonia and Iberia is established. The Digermulen Peninsula has great potential as a reference section for establishing a Cambrian chronostratigraphy based on acritarchs.

We report on new occurrences of the late Ediacaran problematicum Palaeopascichnus (Protista?) from the Stáhpogieddi Formation, Arctic Norway. The stratigraphically lowest occurrences are in beds transitional between the Lillevannet and Indreelva members: the highest in the second cycle of the Manndrapselva Member, stratigraphically close to the lowest occurrences of Cambrian-type trace fossils. This establishes a long stratigraphical range of Palaeopascichnus on the Digermulen Peninsula, as has been previously documented from Newfoundland, South Australia, and elsewhere in Baltica. The age range of Palaeopascichnus in Avalonia and Baltica is from ∼565 to 541 Ma. Since the transition from the Mortensnes Formation to the Stáhpogieddi Formation is without a major break in sedimentation, this supports the inference that the underlying glacigenic Mortensnes Formation is ca. 580 Ma, and therefore Gaskiers-equivalent, or younger.

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New records of phytoplankton (acritarchs), ichnofossils and olenellid trilobites have been studied from the autochthonous upper Neoproterozoic-Lower Cambrian successions along the Caledonian Thrust Front in the Laisvall-Storuman region of northern Sweden. The fossils are from a newly examined natural outcrop at Bergmyrhobben near Lake Storuman, and from previously described fossiliferous outcrops at Delliknäs and Mt. Assjatj, the Laisvall mine and the Maiva borehole successions in the Laisvall area. Acritarch assemblages are recorded throughout the Grammajukku Formation. They are age-diagnostic for the Skiagia-Fimbriaglomerella acritarch Zone, time-equivalent to the Schmidtiellus mickwitzi trilobite Zone (the lower part of the formation), and the Heliosphaeridium-Skiagia acritarch Zone corresponding to the Holmia kjerulfi trilobite Zone (the upper part of the formation). The acritarch record from the Storuman area documents the presence of strata contemporaneous to the Schmidtiellus mickwitzi Zone for the first time in the Scandinavian Caledonides. This zone was previously only recognized in the platform regions of the Baltica palaeocontinent. The ichnofossils from the upper Såvvovare Formation, including ?Harlaniella, Phycodes, Gyrolithes and Palaeophycus ichnogenera, allowed the base of the Cambrian System to be determined within the Maiva Member and the coeval Kautsky Ore Member in the subsurface successions, and to attribute this part of the formation to the Lower Cambrian Platysolenites antiquissimus faunal Zone of Baltica. The trilobite fauna from the Storuman area, attributed tentatively to Holmia sp., occurs at the lowermost stratigraphic level among olenellids in the Caledonides. The range of this species, estimated from the concurrent acritarch biostratigraphy, is within the Schmidtiellus mickwitzi Zone. The stratigraphic significance of the acritarch assemblages and ichnofossils is analysed and the biochronology of the Grammajukku Formation and the upper Såvvovare Formation is discussed in detail in the context of Lower Cambrian zonation in Baltica. ‡Author for correspondence: Malgo.Vidal@pal.uu.se

ABSTRACT. Four Middle and Upper Cambrian burlingiid trilobites from the Oslo Region, Norway, are described including Burlingia angusta sp. nov. from the Ptychagnostus punctuosus Zone and Schmalenseeia athrotryphe sp. nov. from the lower part of the Lejopyge laevigata Zone. New complete material previously attributed to Schmalenseeia jagoi Whittington is assigned to Burlingia. Cladistic analysis supports the genera Burlingia and Schmalenseeia as currently understood, including the placement of the controversial middle Middle Cambrian Schmalenseeia acutangula Westerga Êrd in Schmalenseeia, even though it lacks typical characters of the genus such as the median ridge on the preglabellar ®eld. The analysis also supports burlingiid monophyly, and suggests that Schmalenseeia was derived from a broadly Burlingia-like ancestor, with S. acutangula displaying how the transition may have occurred. The broader relationships of Burlingia remain obscure, although similarities between burlingiids and the arthropod Kleptothule from the Early Cambrian Sirius Passet fauna are discussed: these include overall form, lack of functional hinges in the thorax, and details of the cephalic region. It is unclear whether these similarities represent general progenetic features, are functional convergences or, less likely, represent a genuine relationship.