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Discovered over a century ago, the lower Cambrian (Series 2, Stage 4) Cranbrook Lagerstatte of southeastern British Columbia's Eager Formation is one of the oldest Burgess Shale-type deposits in North America. This Konservat-Lagerstatte is rich in olenelloid trilobites, but also yields a very low-diversity soft-bodied fossil assemblage including Tuzoia and Anomalocaris, and a low-diversity ichnofauna. Its scientific study, however, remains limited. A 2015 field-based investigation by the Royal Ontario Museum has revealed new information about the site's biota, depositional environment and taphonomic conditions. Not only is the Cranbrook Lagerstatte significant for early Cambrian biostratigraphy and comparisons with other Burgess Shale-type deposits, it also reveals some of the little-known diversity of life in a distal outer shelf environment during the Cambrian period.

An Early Ordovician fauna of linguliform brachiopods and euconodonts is described from the Alum Shale Formation in northernmost Vasterbotten County, northern Sweden. The fauna was recovered from a single carbonate concretion collected at an exposure near the northern shore of Lake Storvindeln. Despite of the fragmentary and tectonized preservation of the obtained fossils, at least eight different taxa of linguliform brachiopods and four species of euconodonts could be identified. Among the brachiopods, the ephippelasmatid Pomeraniotreta biernatae Bednarczyk, 1986 is most common; it is associated among others with the acrotretids Eurytreta cf. sabrinae (Callaway, 1877) and Ottenbyella sp., and a spinose specimen potentially representing the zhanatellid Thysanotos. Two of the brachiopod taxa appear to present new species, Pomeraniotreta n. sp. and Mytoella? n. sp., but additional material would be needed for a formal description. Euconodont specimens are rare and comprise coniform elements of Drepanodus arcuatus Pander, 1856, Drepanoistodus aff. amoenus (Lindstrom, 1955) sensu Lofgren (1994), Paroistodus numarcuatus (Lindstrom, 1955) and Rossodus aff. manitouensis Repetski & Ethington, 1983. Evaluation of the stratigraphic distribution of the different taxa of brachiopods and euconodonts under consideration of the local geology, suggests that the investigated sample represents a level in the upper part of the Tremadocian (Tr2) part of the Alum Shale Formation. The fauna represents the northernmost occurrence of age diagnostic Early Ordovician (Tremadocian) fossils in Sweden.

The two major structural elements of the Iberian Chains, the Datos and Jarque thrust faults, have been described as occurring in proximity in the area around the village of Codos. The purported Jarque fault corresponds to the axial plane of an anticline known as the Codos anticline, which exposes the oldest stratigraphic unit in this area, i.e. the Codos Bed, a limestone bed bearing skeletal fossils of putative Ediacaran or earliest Cambrian age. Details of the geology of the area and the age of the known fossils are poorly understood or not universally agreed upon. New investigations in the anticline revealed the presence of a normal fault, introduced as the Codos fault, which cross-cuts the course of the alleged Jarque fault. The vertical displacement along the axial plane of the anticline appears to be insignificant, challenging the traditional interpretation of the plane as an equivalent of the Jarque thrust fault. Reinvestigation of the Codos Bed revealed previously unknown skeletal fossils of early Cambrian age, confirming notions that the bed is younger than traditionally assumed. In particular, two helcionelloid molluscs, Anabarella cf. plana and Igorella? sp., allow correlations with Terreneuvian strata of central Spain (Pusa and Fuentepizzara formations) and support previously suggested connections with the Heraultia Limestone of southern France. Former identification of the terminal Ediacaran index-fossil Cloudina in the bed is erroneous. Consequently, the Ediacaran-Cambrian boundary in the Iberian Chains, which has been placed at the top of the formation overlying the Codos Bed, is stratigraphically distinctly lower.

A new bradoriid fauna comprising seven taxa is introduced from the early Cambrian Skyberg Member of the Ringstrand Formation of the Mjøsa area in Norway. The fauna is compared to coeval specimens described from Sweden (Wiman 1903), which have been restudied for this study. Both faunas comprise the same, or similar, genera of the families Bradoriidae, Beyrichonidae, Hipponicharionidae, and Svealutidae. Reevaluation of Wiman’s specimens revealed the presence of five distinct taxa rather than nine. The faunas from Norway and Sweden are similar to contemporaneous faunas of Avalonia and West Gondwana.

Bulk sampling of middle Cambrian carbonate units in the lower Burgess Shale Formation (Wuliuan) and the upper Wheeler Formation (Drumian) in Utah have yielded abundant silicified stenothecoids. Previously unreported from the Burgess Shale, stenothecoids discovered include at least two species: Stenothecoides cf. elongata and Stenothecoides rasettii sp. nov. The Utah material is assigned to Stenothecoides elongata. The new stenothecoid material confirms some earlier observations including a set of interior grooves and ridges forming nested chevrons across the midline and a finer set disposed around the interior shell margin. The chevroned grooves are interpreted here as mantle canals and the peripheral furrows as setal grooves. A prominent boss occurs at the valve apex in both valves. An apparent socket receiving the boss in the opposite valve described in earlier studies we show to be an artefact of preservation. Consequently, the bosses were juxtaposed when the valves were conjoined and so must have had some function other than valve articulation. Most extraordinary in Stenothecoides is an embayment at the shell apex, which likely represents a rudimentary pedicle foramen. This and other features including apparent articulate brachiopod-like calcitic fibrous shell microstructure replicated in silica, indicate phylogenetic propinquity of the Stenothecoida is with the Brachiopoda, not the Mollusca. However, phylogenetic proximity of the Stenothecoida relative to any of the brachiopod crown groups is unclear. Stenothecoids may represent a pan-brachiopod stem group derived from organocalcitic, multisclerite, eccentrothecimorph tommotiids via sclerite reduction to two opposing mitral sclerites. Discovery of stenothecoids in carbonate debris aprons in the Burgess Shale suggests transport of shelly biota downslope from the adjacent platform. However, their absence in siliciclastic units of the Burgess Shale preserving both shelly and soft-bodied biota indicates these units

The Paracuellos Group is the oldest sedimentary sequence of the Iberian Chains in north-east Spain. The group is subdivided into three formation which are, in stratigraphic order, the Sestrica Formation, known only from drill cores, the Saviñan Formation and the Aluenda Formation (Álvaro & Blanc-Valleron, 2002). The sequence has traditionally been considered as Neoproterozoic in age based on its stratigraphic position (e.g., Lotze, 1961), the occurrence of the trace fossil Torrowangeaaff. roseiWebby in the middle part of the Saviñan Formation (Liñan & Tejero, 1988), and putative fossils of CloudinaGerms in the Aluenda Formation (Streng, 1996; Álvaro & Blanc-Valleron, 2002). The Paracuellos Group is exposed in two geographically separated areas where it forms the core of faulted anticlines, the Paracuellos antiform and the Codos antiform in the in the northwestern and central Eastern Iberian Chains, respectively (Álvaro & Blanc-Valleron, 2002). In the Paracuellos antiform, the boundary between the Paracuellos Group and the overlying Bámbola Formation is represented by an erosive contact and represents a hiatus (Liñan & Tejero, 1988; Álvaro & Blanc-Valleron, 2002). In contrast, in the Codos antiform a more gradual transition between the two formations can be observed (Streng, 1996; Álvaro et al., 2002). The Ediacaran-Cambrian boundary was traditionally placed at the boundary between the Aluenda Formation and the Bámbola Formation. The putative Cloudinafossils have been recovered from a carbonate bed that forms the base of the Aluenda Formation in the Codos antiform, termed the Codos Bed by Álvaro & Blanc-Valleron (2002). However, already at the time of discovery, Streng (1996) pointed out that the tube-shaped fossils lack the characteristic cone-in-cone structure of Cloudina. In addition, cross-sections of a variety of other tube-like small shelly fossils had been observed within the carbonate bed, partly exhibiting internal septate struct

A previously undocumented diversity of Cambrian palaeoscolecids is described from localities in Sweden, Norway and Denmark. The material described here includes isolated sclerites as well as the first macroscopic specimens reported from the palaeocontinent Baltica. The sclerites are all of early middle Cambrian age (Ptychagnostus gibbus Biozone) and are assigned to at least four new species of Hadimopanella, two of which are formally introduced: H. incubo sp. nov. and H. oelandiana sp. nov. The two macroscopic specimens are of late early Cambrian (Ellipsocephalus lunatus Biozone) and early middle Cambrian age (Acadoparadoxides oelandicus Biozone), respectively. The early Cambrian specimen is described as Maotianshania? sp. and comprises an incomplete annulated trunk fragment which is uniformly covered with circular sclerites, indicative of the palaeoscolecid family Maotianshaniidae. This is the first record of this family outside China. The middle Cambrian specimen is almost complete and introduced as Wronascolex? johanssoni sp. nov. It is characterized by a previously undocumented distribution of its Hadimopanella-like sclerites which increase in size and change ornamentation from the anterior to the posterior end of the distinctly annulated trunk. The observed distribution pattern can explain the high variability of species of the sclerite-based genus Hadimopanella as well as the occurrence of rare morphotypes of Hadimopanella in otherwise rich samples. Available data on the ontogeny of palaeoscolecids regarding the relationship between body and sclerite size of a taxon are evaluated. It is concluded that sclerite size might be species specific and should be considered when comparing taxa with morphological similar sclerites.

Volcanic pyroclasts of small size, such as lapilli and small pumice stones, are widely used in agriculture, gardening, and for pot plants as natural inorganic mulch. The technique of using pyroclasts to enhance topsoil stems from the eighteenth century, and specifically from the ad 1730–1736 eruption on Lanzarote. Critical observations on plant development during and after the eruption showed that the vegetation died when buried under a thick layer of lapilli, but grew vigorously when covered thinly. While the agriculture of Lanzarote was restricted to cereals before the eruption, it diversified to many kinds of fruit and vegetables afterwards, including the production of the famous Malvasía wines in the Canaries. The population of Lanzarote doubled in the years after the eruption, from about 5000 in 1730 to near 10 000 in 1768, predominantly as a result of the higher agricultural productivity. This outcome led to widespread use of lapilli and pumice fragments throughout the islands and eventually the rest of the globe. Lapilli and pumice provide vesicle space for moisture to be retained longer within the planting soil, which can create an environment for micro-bacteria to thrive in. Through this route, nutrients from volcanic matter are transported into the surrounding soil where they become available to plant life. The detailed processes that operate within the pyroclasts are less well understood, such as the breakdown of nutrients from the rock matrix and transport into the soil by biological action. Further studies promise significant potential to optimize future agricultural efforts, particularly in otherwise arid areas of the globe.

Circum-Laurentian middle Cambrian (Cambrian Series 3) deposits in Greenland and British Columbia yield a new hipponicharionid bradoriid arthropod, Flumenoglacies n. gen., characterized by a comarginal, ramp-like structure which is crested by a continuous lobe. The narrow lobe is the result of the medial fusion of anterior and posterior lobes, seemingly a recurrent theme in hipponicharionid evolution. The type species, F. groenlandica n. sp., is described from the Ekspedition Brae Formation (Drumian Stage) of Peary Land but the description of two unnamed species from slightly older middle Cambrian strata of the Stephen Formation of British Columbia provides additional evidence for the wide distribution of Small Shelly Faunas during the Cambrian.

Burgess Shale-type fossil assemblages provide the best evidence of the ‘Cambrian explosion’. Here we report the discovery of an extraordinary new soft-bodied fauna from the Burgess Shale. Despite its proximity (ca. 40km) to Walcott’s original locality, the Marble Canyon fossil assemblage is distinct, and offers new insights into the initial diversification of metazoans, their early morphological disparity, and the geographic ranges and longevity of many Cambrian taxa. The arthropod-dominated assemblage is remarkable for its high density and diversity of soft-bodied fossils, as well as for its large proportion of new species (22% of total diversity) and for the preservation of hitherto unreported anatomical features, including in the chordate Metaspriggina and the arthropod Mollisonia. The presence of the stem arthropods Misszhouia and Primicaris, previously known only from the early Cambrian of China, suggests that the palaeogeographic ranges and longevity of Burgess Shale taxa may be underestimated.

Early Middle Cambrian bituminous coquinoid limestones from a tectonically isolated outcrop in southwestern Kyrgyzstan yield a remarkably diverse fauna, with stem-group cnidarians, trilobites, rhynchonelliformean brachiopods, and other shelly fossils. The fossil site is in the northern foothills of the Turkestan Range and thus forms part of the westernmost extension of the South Tien Shan. The fauna includes two fairly well known trilobite species, Glabrella ventrosa Lermontova, 1940 and Dorypyge richthofeniformis Lermontova, 1940, that provide confident support for an Amgan age of the rocks. New described taxa include the stem-group cnidarian Cambroctoconus kyrgyzstanicus Peel sp. nov., the trilobite Olenoides sagittatus Geyer sp. nov., and the helcionelloid Manasoconus bifrons Peel gen. et sp. nov. Additional fossils within the samples include the trilobites Olenoides sp. A, Kootenia sp., and Pseudoeteraspis? sp.; the rhynchonelliform brachiopods Narynella cf. ferganensis (Andreeva, 1962), Narynella? sp., Austrohedra? sp. nov., and two species of uncertain generic affinity; the tommotiid Tesella sp.; the hyolithelminth Hyolithellus sp.; and the palaeoscolecid Hadimopanella oezgueli Gedik, 1977. Of particular interest is Cambroctoconus kyrgyzstanicus with an octagonal corallum and a sparsely septate calyx.

The late Llandovery graptolite fauna of the Retiolites Shales on Kinnekulle Mountain in the province of Västergötland has long been known but never illustrated or studied in detail. New collections of graptolites from an interval at the very top of the exposed succession confirm previous reports of cyrtograptids, which make the shales on Kinnekulle the youngest preserved Palaeozoic rocks in the area. The co-occurrence of Oktavites spiralis and Cyrtograptus lapworthi constrains the strata to the lower lapworthi Biozone of the upper Telychian. The associated graptolite fauna comprises numerous monograptids and Retiolites angustidens as well as Cyrtograptus kinnekullensis n. sp., characterised by its open coiling and the presence of a second-order cladium on the second thecal cladium. This early occurrence of a cyrtograptid species with a second-order cladium on Baltica matches evolutionary patterns observed in Laurentia, suggesting that the ability to grow cladia of both first and higher order evolved approximately, synchronously and at the very beginning of cyrtograptid evolution.

Boreholes in mineralized shells are a widely recognized form of predation throughout the Phanerozoic. In fact, such borings are as old as the first mineralized shells dating back to the Ediacaran. Their occurrence among the earliest skeletal animals has been interpreted that protection against predators was one of the driving forces behind the evolution of mineralized hardparts. Hence, these early traces provide crucial clues in understanding the mysterious emergence of complex multicellular animals. However, new observations made on shells of linguliform brachiopods from the Cambrian of Sweden suggest caution when interpreting perforations in shells as predatory or even as being organic. The recovered acrotretid assemblage is characterized by an unusual frequency of shells bearing circular to irregular circular holes. These holes resemble shell perforations interpreted in the literature as predatory borings and holes produced by a predator using a piercing appendage. However, close examination of the shells reveals the presence of pyrite crystals growing on the shell surfaces and within shell layers, thereby destroying the shell and producing the common perforations. It is proposed that pyrite crystal growth might be responsible for a variety of holes in fossil shells, holes previously interpreted to be predatory.