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We describe the thecideid brachiopod Praelacazella wetherelli (Morris, 1851) from the lower Maastrichtian Korojon Formation in the Carnarvon Basin, Western Australia. This is the first documented record of Praelacazella wetherelli from the Southern Hemisphere, suggesting that the species was cosmopolitan in distribution during the Late Cretaceous. Three possible long-distance migration routes are discussed.

An unusually rich and diverse suite of virgianid brachiopods, hitherto poorly known, is systematically described here for the first time from the Ordovician–Silurian boundary interval (late Katian – Aeronian) of North Greenland. The Late Ordovician virgianids comprise typical taxa of the warm-water Tcherskidium fauna (e.g. Tcherskidium tenuicostatum, Proconchidium schleyi, Holorhynchus giganteus and Deloprosopus dawesi sp. nov.). Among the early Silurian taxa, Virgiana hursti sp. nov. occurs as abundant shell beds, similar to other congeneric species in Laurentia, but has somewhat larger internal skeletal structures, albeit not as extravagantly developed as in the late Katian virgianids; Borealoides balderi gen. et sp. nov. shows extreme thickening of the shell wall and internal structures, approaching the extravagant calcification of Katian virgianids. The highly distinctive mid-Aeronian stricklandioid brachiopod genus, Kulumbella, characterized by a shell with criss-cross (divaricate) ribbing, also occurs in North Greenland, represented by K. heimdali sp. nov., which has the largest and most strongly biconvex shells for the genus. Palaeogeographically, the Late Ordovician virgianid fauna of Laurentia was highly distinct, confined to the low–mid tropical latitudes north of the palaeoequator. In comparison, the early Silurian (Rhuddanian) Virgiana and some related taxa in Laurentia spanned the tropics of both hemispheres, forming extensive shell beds in carbonate basins, although Borealis and Borealoides gen. nov. remained confined largely to the northern hemisphere, suggesting a certain level of provincialism extending into the earliest Silurian. A palaeoecological preference for warm-water carbonate settings would explain the unusual abundance and richness of the virgianid faunas in North Greenland.

We describe the thecideid brachiopod Praelacazella wetherelli (Morris, 1851) from the lower Maastrichtian Korojon Formation in the Carnarvon Basin, Western Australia. This is the first documented record of Praelacazella wetherelli from the Southern Hemisphere, suggesting that the species was cosmopolitan in distribution during the Late Cretaceous. Three possible long-distance migration routes are discussed.

An unusually rich and diverse suite of virgianid brachiopods, hitherto poorly known, is systematically described here for the first time from the Ordovician–Silurian boundary interval (late Katian – Aeronian) of North Greenland. The Late Ordovician virgianids comprise typical taxa of the warm-water Tcherskidium fauna (e.g. Tcherskidium tenuicostatum, Proconchidium schleyi, Holorhynchus giganteus and Deloprosopus dawesi sp. nov.). Among the early Silurian taxa, Virgiana hursti sp. nov. occurs as abundant shell beds, similar to other congeneric species in Laurentia, but has somewhat larger internal skeletal structures, albeit not as extravagantly developed as in the late Katian virgianids; Borealoides balderi gen. et sp. nov. shows extreme thickening of the shell wall and internal structures, approaching the extravagant calcification of Katian virgianids. The highly distinctive mid-Aeronian stricklandioid brachiopod genus, Kulumbella, characterized by a shell with criss-cross (divaricate) ribbing, also occurs in North Greenland, represented by K. heimdali sp. nov., which has the largest and most strongly biconvex shells for the genus. Palaeogeographically, the Late Ordovician virgianid fauna of Laurentia was highly distinct, confined to the low–mid tropical latitudes north of the palaeoequator. In comparison, the early Silurian (Rhuddanian) Virgiana and some related taxa in Laurentia spanned the tropics of both hemispheres, forming extensive shell beds in carbonate basins, although Borealis and Borealoides gen. nov. remained confined largely to the northern hemisphere, suggesting a certain level of provincialism extending into the earliest Silurian. A palaeoecological preference for warm-water carbonate settings would explain the unusual abundance and richness of the virgianid faunas in North Greenland.

Diandongia pista Rong is the thickest-shelled and strongly mineralized of all the brachiopods that have been recorded from the Chengjiang Fauna. It is also one of the most common species in the biota. Previous accounts have concentrated largely on the exceptionally preserved soft-bodied anatomy of this species. Here its detailed internal and external shell morphologies are described for the first time, based on BSEM and SEM observations. Its general shell morphology, pseudointerareas, and pustulose ornamentation are most similar to those of the Botsfordiidae, where many species have a Diandongia-like rhombic pattern of pustules in the juvenile apical region only. On the other hand, other aspects of the muscle pattern and the partly smooth adult ornamentation of D. pista is more suggestive of species within the Neobolidae, like Edreja. The mantle canal system in sub-adults of D. pista is comparable to that of the Eoobolidae and Obolidae, whereas the adult vascular system branches peripherally in dichotomy. D. pista may be the earliest representatives possessing some plesiomorphic characters of the Botsfordiidae.

In this paper a brachiopod fauna (the Miharanoro fauna), consisting of 11 species in 9 genera, is described from the lower Permian limestone (Uyamano Formation) of Miharanoro in the Taishaku area, Akiyoshi Belt, southwestern Japan. The age of the Miharanoro fauna is identified as the Asselian (early Permian, Cisuralian). In terms of palaeobiogeography, the Miharanoro fauna is a mixed Boreal-Tethyan-Panthalassan fauna, and exhibits an affinity with the lower Permian fauna of Texas. Thus, the seamounts of the Akiyoshi Belt, including Taishaku, were probably located between the Sino-Mongolian-Japanese Province and North America (Texas) in Panthalassa during the Asselian., departmental bulletin paper

In this paper a brachiopod fauna (the Miharanoro fauna), consisting of 11 species in 9 genera, is described from the lower Permian limestone (Uyamano Formation) of Miharanoro in the Taishaku area, Akiyoshi Belt, southwestern Japan. The age of the Miharanoro fauna is identified as the Asselian (early Permian, Cisuralian). In terms of palaeobiogeography, the Miharanoro fauna is a mixed Boreal-Tethyan-Panthalassan fauna, and exhibits an affinity with the lower Permian fauna of Texas. Thus, the seamounts of the Akiyoshi Belt, including Taishaku, were probably located between the Sino-Mongolian-Japanese Province and North America (Texas) in Panthalassa during the Asselian.

The last clade-level extinction episode affecting the Phylum Brachiopoda has been long-established in the Early Toarcian Mass Extinction Event (ETMEE) around the Pliensbachian-Toarcian transition, when several rhynchonellide groups became extinct and others underwent a notable renewal in the western Tethys. Among them, Wellerelloidea is a long-ranging superfamily severely affected by this environmental crisis, embodying the subfamily Cirpinae as the last wellerelloids worldwide, prior to their global extinction in the Pb-To transition. The profuse record of Lower Jurassic cirpines in the peri-Iberian paleomargins provides an opportunity to clarify the taxonomy of wellerelloid species in the pre-extinction interval. A new species (Cirpa lucentina) is erected and the revision of the Cirpinae taxa around the ETMEE is carried out. Morphometric analysis and the study of internal structures of the shells support separation of the genera Cirpa and Salgirella, adding new supplementary diagnostic criteria. The biogeographic distribution of this clade in the western Tethys and its evolutionary history in the Early Jurassic reveal a pervasive colonization pattern of both epicontinental and epioceanic habitats. The Mediterranean origin of the last representatives of this group is ascertained, but while diversification of Salgirella took place in epioceanic habitats, speciation of Cirpa is unrelated to biochorema boundaries, even colonizing epicontinental seas until their extinction prior to the hyperwarming event that occurred in the basal Serpentinum Zone. A rhynchonellide morphogroup epitomized by cirpines was resilient to this event in the epicontinental seas. This morphogroup is also recorded after the extinction interval by means of the genus Pseudogibbirhynchia, thus postulating potential pre- and post-extinction phyletic relationships.

Organyà (Lérida prov., NE Spain) (Aptian) is cited as new locality for Gemmarcula crassicosta. A list of associated fauna (pars) is given., Se cita Organyà (Prov. Lérida) (Aptiense) como nueva localidad para Gemmarcula crassicosta. Se enumera parte de la fauna asociada.

An early Permian brachiopod fauna consisting of nine species in eight genera with Jilinmartinia shansiensis is described from the basal part of the Mizuyagadani Formation, Fukuji in the Hida Gaien Belt, central Japan. The brachiopod fauna (Mizuyagadani fauna) is assigned to the Sakmarian. In terms of palaeobiogeography, the fauna is a mixed Boreal-Tethyan fauna, and has affinity with those of northwestern China (Xinjiang and Gansu) and northern China (Shanxi). Thus, the Mizuyagadani fauna probably belonged to the Sino-Mongolian-Japanese Province, and the Hida Gaien region, including Fukuji, was probably located near and to the northeast of the North China Block during the Sakmarian.

An early Permian brachiopod fauna consisting of nine species in eight genera with Jilinmartinia shansiensis is described from the basal part of the Mizuyagadani Formation, Fukuji in the Hida Gaien Belt, central Japan. The brachiopod fauna (Mizuyagadani fauna) is assigned to the Sakmarian. In terms of palaeobiogeography, the fauna is a mixed Boreal-Tethyan fauna, and has affinity with those of northwestern China (Xinjiang and Gansu) and northern China (Shanxi). Thus, the Mizuyagadani fauna probably belonged to the Sino-Mongolian-Japanese Province, and the Hida Gaien region, including Fukuji, was probably located near and to the northeast of the North China Block during the Sakmarian., departmental bulletin paper

An early Permian brachiopod fauna consisting of nine species in eight genera with Jilinmartinia shansiensis is described from the basal part of the Mizuyagadani Formation, Fukuji in the Hida Gaien Belt, central Japan. The brachiopod fauna (Mizuyagadani fauna) is assigned to the Sakmarian. In terms of palaeobiogeography, the fauna is a mixed Boreal-Tethyan fauna, and has affinity with those of northwestern China (Xinjiang and Gansu) and northern China (Shanxi). Thus, the Mizuyagadani fauna probably belonged to the Sino-Mongolian-Japanese Province, and the Hida Gaien region, including Fukuji, was probably located near and to the northeast of the North China Block during the Sakmarian.

Organyà (Lérida prov., NE Spain) (Aptian) is cited as new locality for Gemmarcula crassicosta. A list of associated fauna (pars) is given., Se cita Organyà (Prov. Lérida) (Aptiense) como nueva localidad para Gemmarcula crassicosta. Se enumera parte de la fauna asociada.

The last clade-level extinction episode affecting the Phylum Brachiopoda has been long-established in the Early Toarcian Mass Extinction Event (ETMEE) around the Pliensbachian-Toarcian transition, when several rhynchonellide groups became extinct and others underwent a notable renewal in the western Tethys. Among them, Wellerelloidea is a long-ranging superfamily severely affected by this environmental crisis, embodying the subfamily Cirpinae as the last wellerelloids worldwide, prior to their global extinction in the Pb-To transition. The profuse record of Lower Jurassic cirpines in the peri-Iberian paleomargins provides an opportunity to clarify the taxonomy of wellerelloid species in the pre-extinction interval. A new species (Cirpa lucentina) is erected and the revision of the Cirpinae taxa around the ETMEE is carried out. Morphometric analysis and the study of internal structures of the shells support separation of the genera Cirpa and Salgirella, adding new supplementary diagnostic criteria. The biogeographic distribution of this clade in the western Tethys and its evolutionary history in the Early Jurassic reveal a pervasive colonization pattern of both epicontinental and epioceanic habitats. The Mediterranean origin of the last representatives of this group is ascertained, but while diversification of Salgirella took place in epioceanic habitats, speciation of Cirpa is unrelated to biochorema boundaries, even colonizing epicontinental seas until their extinction prior to the hyperwarming event that occurred in the basal Serpentinum Zone. A rhynchonellide morphogroup epitomized by cirpines was resilient to this event in the epicontinental seas. This morphogroup is also recorded after the extinction interval by means of the genus Pseudogibbirhynchia, thus postulating potential pre- and post-extinction phyletic relationships.

In the westernmost Tethys, the Early Jurassic involved critical environmental changes affecting marine ecosystems. Brachiopods were particularly affected in the South-Iberian Palaeomargin. A late Sinemurian-early Pliensbachian tectonic event led to the collapse of shallow platforms related to the Atlantic Ocean opening. Subsequently, the early Toarcian Extinction Event occurred during a carbon cycle perturbation and the development of oxygen-depleted conditions, mainly affecting benthic communities. In the Subbetic Domain, brachiopod dynamics concur with these major environmental perturbation events. Geochemical imprint of brachiopod shells from this area has been analyzed revealing a clear synchrony between oscillations of trace elements content, global trends in the C and O cycling, and faunal diversity dynamics around critical bioevents, allowing to validate global and regional models related to the platform collapse and the early Toarcian biotic crisis. In the Sinemurian-Pliensbachian turnover and the Toarcian crisis, the redox-sensitive trace metals, REEs, and Fe content in the brachiopod shells show positive excursions. Nevertheless, their trend together with brachiopod diversity patterns, the lower TOC values, and the sedimentary data, support that oxygen depletion must have played a secondary role as environmental stress factor for the benthic fauna. Instead, an increasing temperature gradient is invoked to have played a decisive role, as demonstrated by the main faunal turnover and replacement events correlating with the palaeotemperatures from the peri-Iberian platforms. Shifts on palaeoproductivity, continental influx, and hydrothermal input are also deduced by the increasing concentrations of several trace elements, interpreted as complementary triggering factors of these Early Jurassic bioevents in the westernmost Tethys Ocean., En el Jurásico Inferior se registran diversos eventos críticos que influyeron significativamente en los ecosistemas marinos del Tethys occidental. Entre las comunidades bentónicas, en el Paleomargen Sudibérico, los braquiópodos se vieron particularmente afectados por dichos eventos. El episodio tectono-sedimentario distensivo asociado a la apertura del proto-Atlántico conllevó el colapso de las amplias plataformas someras imperantes en el Tethys hasta el Sinemuriense superior-Pliensbaquiense basal, con la consiguiente reorganización de los ecoespacios faunísticos. Posteriormente, el evento de extinción registrado en el Toarciense inferior, trajo consigo importantes alteraciones en el ciclo del carbono así como el desarrollo de condiciones anóxicas que afectaron principalmente a las comunidades bentónicas. En el dominio Subbético, la dinámica poblacional de los braquiópodos coincidió con estos importantes eventos de perturbación ambiental. Se ha analizado la impronta geoquímica registrada en conchas de braquiópodos del Subbético oriental, revelando una clara sincronía entre las oscilaciones del contenido en elementos traza, las tendencias globales en el ciclo del C y del O y la diversidad de la braquiofauna en torno a dichos eventos críticos, lo que permite validar modelos globales y regionales relacionados tanto con el evento de rifting incipiente de las plataformas someras en el Sinemuriense-Pliensbachiense, como con la crisis biótica global en torno al Toarciense inferior. En la renovación faunística verificada para el tránsito Sinemuriense-Pliensbachiense y para el evento de extinción del Toarciense, los metales traza sensibles a las condiciones redox, la concentración de REE y el contenido en Fe en las conchas de braquiópodos muestran excursiones positivas. Esta tendencia, junto a los patrones de diversidad de los braquiópodos, los bajos valores de TOC y las evidencias sedimentarias, sugieren que, en esta región, la anoxia debió representar un factor secundario

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

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 extraordinary window of phosphatized and phosphatic small shelly fossils (SSF) during the early and middle Cambrian is an important testament to the radiation of biomineralizing metazoans. While SSF are well known from most Cambrian palaeocontinents during this time interval, western Laurentia has relatively few SSF faunas. Here we describe a diverse SSF fauna from the early Cambrian (Stages 3–4) Mural Formation at three localities in Alberta and British Columbia, Canada, complemented by carbon isotope measurements to aid in a potential future bio-chemostratigraphic framework. The fauna expands the recorded SSF assemblage diversity in western Laurentia and includes several brachiopods, four bradoriids, three chancelloriids, two hyoliths, a tommotiid and a helcionellid mollusc as well as echinoderm ossicles and specimens of Microdictyon, Volborthella and Hyolithellus. New taxa include the tommotiid genus Canadiella gen. nov., the new bradoriid species Hipponicharion perforata sp. nov. and Pseudobeyrichona taurata sp. nov. Compared with contemporaneous faunas from western Laurentia, the fauna is relatively diverse, particularly in taxa with originally phosphatic shells, which appear to be associated with archaeocyathid build-ups. This suggests that the generally low faunal diversity in western Laurentia may be at least partly a consequence of poor sampling of suitable archaeocyathan reef environments. In addition, the tommotiid Canadiella filigrana appears to be of biostratigraphical significance in Cambrian Stage 3 strata of western Laurentia, and the unexpected high diversity of bradoriid arthropods in the fauna also suggests that this group may prove useful for biostratigraphical resolution in the region.

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 extraordinary window of phosphatized and phosphatic small shelly fossils (SSF) during the early and middle Cambrian is an important testament to the radiation of biomineralizing metazoans. While SSF are well known from most Cambrian palaeocontinents during this time interval, western Laurentia has relatively few SSF faunas. Here we describe a diverse SSF fauna from the early Cambrian (Stages 3–4) Mural Formation at three localities in Alberta and British Columbia, Canada, complemented by carbon isotope measurements to aid in a potential future bio-chemostratigraphic framework. The fauna expands the recorded SSF assemblage diversity in western Laurentia and includes several brachiopods, four bradoriids, three chancelloriids, two hyoliths, a tommotiid and a helcionellid mollusc as well as echinoderm ossicles and specimens of Microdictyon, Volborthella and Hyolithellus. New taxa include the tommotiid genus Canadiella gen. nov., the new bradoriid species Hipponicharion perforata sp. nov. and Pseudobeyrichona taurata sp. nov. Compared with contemporaneous faunas from western Laurentia, the fauna is relatively diverse, particularly in taxa with originally phosphatic shells, which appear to be associated with archaeocyathid build-ups. This suggests that the generally low faunal diversity in western Laurentia may be at least partly a consequence of poor sampling of suitable archaeocyathan reef environments. In addition, the tommotiid Canadiella filigrana appears to be of biostratigraphical significance in Cambrian Stage 3 strata of western Laurentia, and the unexpected high diversity of bradoriid arthropods in the fauna also suggests that this group may prove useful for biostratigraphical resolution in the region.

A productid brachiopod species, Latiproductus edelburgensis (Phillips), is described from the upper Visean to lower Serpukhovian of the Akiyoshi Limestone, Akiyoshi, southwest Japan and the Omi Limestone, Omi, central Japan. The occurrence of L. edelburgensis indicates a late Visean to early Serpukhovian age for the Mediocris mediocris Zone of the Akiyoshi Limestone and the Eostaffella‒Millerella Zone of the Omi Limestone. The stratigraphic and geographic distributions of L. edelburgensis are restricted to the Lower Carboniferous (upper Visean to lower Serpukhovian) of Europe, central and eastern Asia, northern Africa and western Panthalassa, and completely absent in North and South America and Australia.

A productid brachiopod species, Latiproductus edelburgensis (Phillips), is described from the upper Visean to lower Serpukhovian of the Akiyoshi Limestone, Akiyoshi, southwest Japan and the Omi Limestone, Omi, central Japan. The occurrence of L. edelburgensis indicates a late Visean to early Serpukhovian age for the Mediocris mediocris Zone of the Akiyoshi Limestone and the Eostaffella‒Millerella Zone of the Omi Limestone. The stratigraphic and geographic distributions of L. edelburgensis are restricted to the Lower Carboniferous (upper Visean to lower Serpukhovian) of Europe, central and eastern Asia, northern Africa and western Panthalassa, and completely absent in North and South America and Australia., departmental bulletin paper

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

In the westernmost Tethys, the Early Jurassic involved critical environmental changes affecting marine ecosystems. Brachiopods were particularly affected in the South-Iberian Palaeomargin. A late Sinemurian-early Pliensbachian tectonic event led to the collapse of shallow platforms related to the Atlantic Ocean opening. Subsequently, the early Toarcian Extinction Event occurred during a carbon cycle perturbation and the development of oxygen-depleted conditions, mainly affecting benthic communities. In the Subbetic Domain, brachiopod dynamics concur with these major environmental perturbation events. Geochemical imprint of brachiopod shells from this area has been analyzed revealing a clear synchrony between oscillations of trace elements content, global trends in the C and O cycling, and faunal diversity dynamics around critical bioevents, allowing to validate global and regional models related to the platform collapse and the early Toarcian biotic crisis. In the Sinemurian-Pliensbachian turnover and the Toarcian crisis, the redox-sensitive trace metals, REEs, and Fe content in the brachiopod shells show positive excursions. Nevertheless, their trend together with brachiopod diversity patterns, the lower TOC values, and the sedimentary data, support that oxygen depletion must have played a secondary role as environmental stress factor for the benthic fauna. Instead, an increasing temperature gradient is invoked to have played a decisive role, as demonstrated by the main faunal turnover and replacement events correlating with the palaeotemperatures from the peri-Iberian platforms. Shifts on palaeoproductivity, continental influx, and hydrothermal input are also deduced by the increasing concentrations of several trace elements, interpreted as complementary triggering factors of these Early Jurassic bioevents in the westernmost Tethys Ocean., En el Jurásico Inferior se registran diversos eventos críticos que influyeron significativamente en los ecosistemas marinos del Tethys occidental. Entre las comunidades bentónicas, en el Paleomargen Sudibérico, los braquiópodos se vieron particularmente afectados por dichos eventos. El episodio tectono-sedimentario distensivo asociado a la apertura del proto-Atlántico conllevó el colapso de las amplias plataformas someras imperantes en el Tethys hasta el Sinemuriense superior-Pliensbaquiense basal, con la consiguiente reorganización de los ecoespacios faunísticos. Posteriormente, el evento de extinción registrado en el Toarciense inferior, trajo consigo importantes alteraciones en el ciclo del carbono así como el desarrollo de condiciones anóxicas que afectaron principalmente a las comunidades bentónicas. En el dominio Subbético, la dinámica poblacional de los braquiópodos coincidió con estos importantes eventos de perturbación ambiental. Se ha analizado la impronta geoquímica registrada en conchas de braquiópodos del Subbético oriental, revelando una clara sincronía entre las oscilaciones del contenido en elementos traza, las tendencias globales en el ciclo del C y del O y la diversidad de la braquiofauna en torno a dichos eventos críticos, lo que permite validar modelos globales y regionales relacionados tanto con el evento de rifting incipiente de las plataformas someras en el Sinemuriense-Pliensbachiense, como con la crisis biótica global en torno al Toarciense inferior. En la renovación faunística verificada para el tránsito Sinemuriense-Pliensbachiense y para el evento de extinción del Toarciense, los metales traza sensibles a las condiciones redox, la concentración de REE y el contenido en Fe en las conchas de braquiópodos muestran excursiones positivas. Esta tendencia, junto a los patrones de diversidad de los braquiópodos, los bajos valores de TOC y las evidencias sedimentarias, sugieren que, en esta región, la anoxia debió representar un factor secundario

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

Genetic control undoubtedly plays the most decisive role in the development of characters in rhynchonellides, especially in those structural features such as shell microstructure and brachidial architecture. However, considering the relationship between shell microstructure and type of crura in post-Palaeozoic rhynchonellides supported by recent growing research, the present study links this striking matching to the distribution of rhynchonellide morphogroups around the main post-Palaeozoic mass extinction and diversification events, innovatively introducing the ribbing pattern as a feature widely argued as indicator of deeper/shallower habitats and particular ecological conditions. The analyses performed on the Western Tethys rhynchonellide database and, directly on 28 species from the peri-Iberian margins around selected post-Palaeozoic extinction/diversification episodes, reveal a recurrent distribution pattern according to the habitat considered (epicontinental vs. epioceanic). The smooth, eurinoid, septifal/arcual body plan is the distinctive inhabitant of deeper epioceanic environments, also being the last to withdraw from the epicontinental platforms when the environmental conditions were adverse, and the pioneers or opportunistic taxa conducting repopulation of these epicontinental habitats when the conditions were re-established after crises. The ribbed, eurinoid, falciform morphogroup seems to be the more resilient stock on epicontinental platforms in relation to ecological crises. Conversely, the ribbed, leptinoid, raducal group is typical inhabitant of epicontinental seas when normal conditions prevail and shows an uneven distribution unlinked to critical events, suggesting a more specialist pattern with a diversification related with a secondary differentiation. It is suggested that this distribution dynamic of morphogroups was controlled by the availability of requirements to generate each type of crura and microstructure in epicontinental/epioceanic h, Ministerio de Economía y Competitividad (MINECO), Universidad de Alicante, Depto. de Geodinámica, Estratigrafía y Paleontología, Fac. de Ciencias Geológicas, TRUE, pub

A moderately diverse assemblage of micromorphic linguliform brachiopods, including Tapuritreta gribovensis sp. nov., Wahwahlingula? pankovensis sp. nov., Acrothele sp., Anabolotreta? sp., Orbithele? sp. and Stilpnotreta sp., is for the first time described from the Cambrian Karpinsk Formation (Miaolingian, Guzhangian) of the South Island of Novaya Zemlya. The morphology of the metamorphic shell in Acrothele and Wahwahlingula? suggest that both taxa had a single pair of larval setal sacs, similar to the recent discinids, but their metamorphosis was completed only at the end of the pelagic stage and shows that they did have direct development, which is characteristic of all recent lingulides. The biogeographical signature of the new Cambrian brachiopod fauna from Novaya Zemlya is discussed, and the new fauna gives new information on the poorly known Cambrian margins of the Baltica palaeocontinent.

New records of the poorly known acrotretid (Biernatidae) microbrachiopod Opsiconidion minor Popov are described from middle Emsian strata of the Ogilvie Formation in east­central Alaska and the adjacent Yukon Territory, Canada, and compared with new better­preserved topotypes from the late Early Devonian (Emsian) of Novaya Zemlya, Russia. In Alaska O. minor occurs together with fragmentary material of Lingulipora sp. and an indeterminate discinid. The only other previous record of O. minor, outside the type area, comes from the Early to ?Middle Devonian (Pragian to ?Givetian) of Australia (Victoria and NSW). Opsiconidion Ludvigsen is a stratigraphically extremely long­ranging and cosmopolitan acrotretid, which exhibits a remarkable conservatism; the morphology of the ventral valve remains essentially unchanged from the earliest Ordovician (Darriwilian) records to the Devonian.

A moderately diverse assemblage of micromorphic linguliform brachiopods, including Tapuritreta gribovensis sp. nov., Wahwahlingula? pankovensis sp. nov., Acrothele sp., Anabolotreta? sp., Orbithele? sp. and Stilpnotreta sp., is for the first time described from the Cambrian Karpinsk Formation (Miaolingian, Guzhangian) of the South Island of Novaya Zemlya. The morphology of the metamorphic shell in Acrothele and Wahwahlingula? suggest that both taxa had a single pair of larval setal sacs, similar to the recent discinids, but their metamorphosis was completed only at the end of the pelagic stage and shows that they did have direct development, which is characteristic of all recent lingulides. The biogeographical signature of the new Cambrian brachiopod fauna from Novaya Zemlya is discussed, and the new fauna gives new information on the poorly known Cambrian margins of the Baltica palaeocontinent.

A moderately diverse assemblage of micromorphic linguliform brachiopods, including Tapuritreta gribovensis sp. nov., Wahwahlingula? pankovensis sp. nov., Acrothele sp., Anabolotreta? sp., Orbithele? sp. and Stilpnotreta sp., is for the first time described from the Cambrian Karpinsk Formation (Miaolingian, Guzhangian) of the South Island of Novaya Zemlya. The morphology of the metamorphic shell in Acrothele and Wahwahlingula? suggest that both taxa had a single pair of larval setal sacs, similar to the recent discinids, but their metamorphosis was completed only at the end of the pelagic stage and shows that they did have direct development, which is characteristic of all recent lingulides. The biogeographical signature of the new Cambrian brachiopod fauna from Novaya Zemlya is discussed, and the new fauna gives new information on the poorly known Cambrian margins of the Baltica palaeocontinent.

New records of the poorly known acrotretid (Biernatidae) microbrachiopod Opsiconidion minor Popov are described from middle Emsian strata of the Ogilvie Formation in east­central Alaska and the adjacent Yukon Territory, Canada, and compared with new better­preserved topotypes from the late Early Devonian (Emsian) of Novaya Zemlya, Russia. In Alaska O. minor occurs together with fragmentary material of Lingulipora sp. and an indeterminate discinid. The only other previous record of O. minor, outside the type area, comes from the Early to ?Middle Devonian (Pragian to ?Givetian) of Australia (Victoria and NSW). Opsiconidion Ludvigsen is a stratigraphically extremely long­ranging and cosmopolitan acrotretid, which exhibits a remarkable conservatism; the morphology of the ventral valve remains essentially unchanged from the earliest Ordovician (Darriwilian) records to the Devonian.

New records of the poorly known acrotretid (Biernatidae) microbrachiopod Opsiconidion minor Popov are described from middle Emsian strata of the Ogilvie Formation in east­central Alaska and the adjacent Yukon Territory, Canada, and compared with new better­preserved topotypes from the late Early Devonian (Emsian) of Novaya Zemlya, Russia. In Alaska O. minor occurs together with fragmentary material of Lingulipora sp. and an indeterminate discinid. The only other previous record of O. minor, outside the type area, comes from the Early to ?Middle Devonian (Pragian to ?Givetian) of Australia (Victoria and NSW). Opsiconidion Ludvigsen is a stratigraphically extremely long­ranging and cosmopolitan acrotretid, which exhibits a remarkable conservatism; the morphology of the ventral valve remains essentially unchanged from the earliest Ordovician (Darriwilian) records to the Devonian.

Genetic control undoubtedly plays the most decisive role in the development of characters in rhynchonellides, especially in those structural features such as shell microstructure and brachidial architecture. However, considering the relationship between shell microstructure and type of crura in post-Palaeozoic rhynchonellides supported by recent growing research, the present study links this striking matching to the distribution of rhynchonellide morphogroups around the main post-Palaeozoic mass extinction and diversification events, innovatively introducing the ribbing pattern as a feature widely argued as indicator of deeper/shallower habitats and particular ecological conditions. The analyses performed on the Western Tethys rhynchonellide database and, directly on 28 species from the peri-Iberian margins around selected post-Palaeozoic extinction/diversification episodes, reveal a recurrent distribution pattern according to the habitat considered (epicontinental vs. epioceanic). The smooth, eurinoid, septifal/arcual body plan is the distinctive inhabitant of deeper epioceanic environments, also being the last to withdraw from the epicontinental platforms when the environmental conditions were adverse, and the pioneers or opportunistic taxa conducting repopulation of these epicontinental habitats when the conditions were re-established after crises. The ribbed, eurinoid, falciform morphogroup seems to be the more resilient stock on epicontinental platforms in relation to ecological crises. Conversely, the ribbed, leptinoid, raducal group is typical inhabitant of epicontinental seas when normal conditions prevail and shows an uneven distribution unlinked to critical events, suggesting a more specialist pattern with a diversification related with a secondary differentiation. It is suggested that this distribution dynamic of morphogroups was controlled by the availability of requirements to generate each type of crura and microstructure in epicontinental/epioceanic h

New records of the poorly known acrotretid (Biernatidae) microbrachiopod Opsiconidion minor Popov are described from middle Emsian strata of the Ogilvie Formation in east­central Alaska and the adjacent Yukon Territory, Canada, and compared with new better­preserved topotypes from the late Early Devonian (Emsian) of Novaya Zemlya, Russia. In Alaska O. minor occurs together with fragmentary material of Lingulipora sp. and an indeterminate discinid. The only other previous record of O. minor, outside the type area, comes from the Early to ?Middle Devonian (Pragian to ?Givetian) of Australia (Victoria and NSW). Opsiconidion Ludvigsen is a stratigraphically extremely long­ranging and cosmopolitan acrotretid, which exhibits a remarkable conservatism; the morphology of the ventral valve remains essentially unchanged from the earliest Ordovician (Darriwilian) records to the Devonian.

It has been reported that two brachiopod species, namely, productid Karavankina sp. and spiriferid Choristites sp., occur from felsic tuff beds correlated to the Arakigawa Formation of the Hida Gaien belt, central Japan. Since previous studies have focused primarily on paleobiogeography and only secondarily on description, we reexamined morphological details of these fossils using clear photographic images. For each species, there only exists a ventral valve specimen but morphological features are present to determine the genera. The examined specimen of Karavankina sp. is characterized by concentric bands and rugae with numerous regularly arranged spines on the external surface of the ventral valve, while the arrangement of the long spines is altered on the marginal rugae, a trait which appears to be unique to this species. The examined Choristites sp. has a pair of dental plates (adminicula) enclosing the adductor and diductor muscle scars on the ventral floor.

A brachiopod fauna (the Onimaru fauna), consisting of six species in five genera, is described from the Onimaru Formation in the Nagaiwa?Onimaru area, South Kitakami Belt, northeastern Japan. The age of the fauna is identified as the late Visean. Palaeobiogeographically, the Onimaru fauna has a close affinity with the lower Carboniferous faunas of southwestern Japan (Akiyoshi Belt), northern Russia (northern Urals), England, Kazakhstan and northwestern China (Xinjiang and Qinghai). The South Kitakami region was probably the eastern extension of the North China Province, and located near and to the east of the North China Block in the late Visean.

It has been reported that two brachiopod species, namely, productid Karavankina sp. and spiriferid Choristites sp., occur from felsic tuff beds correlated to the Arakigawa Formation of the Hida Gaien belt, central Japan. Since previous studies have focused primarily on paleobiogeography and only secondarily on description, we reexamined morphological details of these fossils using clear photographic images. For each species, there only exists a ventral valve specimen but morphological features are present to determine the genera. The examined specimen of Karavankina sp. is characterized by concentric bands and rugae with numerous regularly arranged spines on the external surface of the ventral valve, while the arrangement of the long spines is altered on the marginal rugae, a trait which appears to be unique to this species. The examined Choristites sp. has a pair of dental plates (adminicula) enclosing the adductor and diductor muscle scars on the ventral floor., departmental bulletin paper

A brachiopod fauna (the Onimaru fauna), consisting of six species in five genera, is described from the Onimaru Formation in the Nagaiwa?Onimaru area, South Kitakami Belt, northeastern Japan. The age of the fauna is identified as the late Visean. Palaeobiogeographically, the Onimaru fauna has a close affinity with the lower Carboniferous faunas of southwestern Japan (Akiyoshi Belt), northern Russia (northern Urals), England, Kazakhstan and northwestern China (Xinjiang and Qinghai). The South Kitakami region was probably the eastern extension of the North China Province, and located near and to the east of the North China Block in the late Visean., departmental bulletin paper

A moderately diverse assemblage of micromorphic linguliform brachiopods, including Tapuritreta gribovensis sp. nov., Wahwahlingula? pankovensis sp. nov., Acrothele sp., Anabolotreta? sp., Orbithele? sp. and Stilpnotreta sp., is for the first time described from the Cambrian Karpinsk Formation (Miaolingian, Guzhangian) of the South Island of Novaya Zemlya. The morphology of the metamorphic shell in Acrothele and Wahwahlingula? suggest that both taxa had a single pair of larval setal sacs, similar to the recent discinids, but their metamorphosis was completed only at the end of the pelagic stage and shows that they did have direct development, which is characteristic of all recent lingulides. The biogeographical signature of the new Cambrian brachiopod fauna from Novaya Zemlya is discussed, and the new fauna gives new information on the poorly known Cambrian margins of the Baltica palaeocontinent.

New records of the poorly known acrotretid (Biernatidae) microbrachiopod Opsiconidion minor Popov are described from middle Emsian strata of the Ogilvie Formation in east­central Alaska and the adjacent Yukon Territory, Canada, and compared with new better­preserved topotypes from the late Early Devonian (Emsian) of Novaya Zemlya, Russia. In Alaska O. minor occurs together with fragmentary material of Lingulipora sp. and an indeterminate discinid. The only other previous record of O. minor, outside the type area, comes from the Early to ?Middle Devonian (Pragian to ?Givetian) of Australia (Victoria and NSW). Opsiconidion Ludvigsen is a stratigraphically extremely long­ranging and cosmopolitan acrotretid, which exhibits a remarkable conservatism; the morphology of the ventral valve remains essentially unchanged from the earliest Ordovician (Darriwilian) records to the Devonian.

Genetic control undoubtedly plays the most decisive role in the development of characters in rhynchonellides, especially in those structural features such as shell microstructure and brachidial architecture. However, considering the relationship between shell microstructure and type of crura in post-Palaeozoic rhynchonellides supported by recent growing research, the present study links this striking matching to the distribution of rhynchonellide morphogroups around the main post-Palaeozoic mass extinction and diversification events, innovatively introducing the ribbing pattern as a feature widely argued as indicator of deeper/shallower habitats and particular ecological conditions. The analyses performed on the Western Tethys rhynchonellide database and, directly on 28 species from the peri-Iberian margins around selected post-Palaeozoic extinction/diversification episodes, reveal a recurrent distribution pattern according to the habitat considered (epicontinental vs. epioceanic). The smooth, eurinoid, septifal/arcual body plan is the distinctive inhabitant of deeper epioceanic environments, also being the last to withdraw from the epicontinental platforms when the environmental conditions were adverse, and the pioneers or opportunistic taxa conducting repopulation of these epicontinental habitats when the conditions were re-established after crises. The ribbed, eurinoid, falciform morphogroup seems to be the more resilient stock on epicontinental platforms in relation to ecological crises. Conversely, the ribbed, leptinoid, raducal group is typical inhabitant of epicontinental seas when normal conditions prevail and shows an uneven distribution unlinked to critical events, suggesting a more specialist pattern with a diversification related with a secondary differentiation. It is suggested that this distribution dynamic of morphogroups was controlled by the availability of requirements to generate each type of crura and microstructure in epicontinental/epioceanic h

A moderately diverse assemblage of micromorphic linguliform brachiopods, including Tapuritreta gribovensis sp. nov., Wahwahlingula? pankovensis sp. nov., Acrothele sp., Anabolotreta? sp., Orbithele? sp. and Stilpnotreta sp., is for the first time described from the Cambrian Karpinsk Formation (Miaolingian, Guzhangian) of the South Island of Novaya Zemlya. The morphology of the metamorphic shell in Acrothele and Wahwahlingula? suggest that both taxa had a single pair of larval setal sacs, similar to the recent discinids, but their metamorphosis was completed only at the end of the pelagic stage and shows that they did have direct development, which is characteristic of all recent lingulides. The biogeographical signature of the new Cambrian brachiopod fauna from Novaya Zemlya is discussed, and the new fauna gives new information on the poorly known Cambrian margins of the Baltica palaeocontinent.

New records of the poorly known acrotretid (Biernatidae) microbrachiopod Opsiconidion minor Popov are described from middle Emsian strata of the Ogilvie Formation in east­central Alaska and the adjacent Yukon Territory, Canada, and compared with new better­preserved topotypes from the late Early Devonian (Emsian) of Novaya Zemlya, Russia. In Alaska O. minor occurs together with fragmentary material of Lingulipora sp. and an indeterminate discinid. The only other previous record of O. minor, outside the type area, comes from the Early to ?Middle Devonian (Pragian to ?Givetian) of Australia (Victoria and NSW). Opsiconidion Ludvigsen is a stratigraphically extremely long­ranging and cosmopolitan acrotretid, which exhibits a remarkable conservatism; the morphology of the ventral valve remains essentially unchanged from the earliest Ordovician (Darriwilian) records to the Devonian.

A comprehensive review and phylogenetic analysis of genera and species presently assigned to the rhynchonelliform superfamily Nisusioidea and family Nisusiidae suggests that this short-lived but important group of brachiopods first appeared in peri-Gondwana during the second half of the Cambrian Series 2, before going extinct by the end of Drumian times. Nisusiides achieved their maximum morphological disparity and geographical distribution during the Wuliuan Age, and Laurentia was probably the major centre of their dispersal. A new phylogenetic analysis suggests an early separation of the lineages of spinose and non-spinose nisusiids. The non-spinose nisusiids probably evolved in Laurentia by the end of Cambrian Series 4. The new nisusiid genus Bellistrophia is described. The new species Nisusia multicostata represents the first documented rhynchonelliform (kutorginide) brachiopod from the Miaolingian (Drumian) of the Alborz Mountains, Iran.

The lower Cambrian (Series 2) White Point Conglomerate (WPC) on Kangaroo Island, South Australia contains exotic clasts representing a diverse array of lithologies, including metamorphics, chert, sandstone, and abundant carbonates, notably archaeocyath-rich bioclastic limestone. Acetic acid digestion of the WPC bioclastic limestone clasts reveals a diverse shelly fauna. This assemblage includes abundant organophosphatic brachiopods such as Cordatia erinae Brock and Claybourn gen. et sp. nov., Curdus pararaensis, Eodicellomus elkaniformiis, Eohadrotreta sp. cf. E. zhenbaensis, Eoobolus sp., Kyrshabaktella davidii, and Schizopholis yorkensis. Additional shelly taxa include the solenopleurid trilobite Trachoparia? sp., the tommotiids Dailyatia odyssei, Dailyatia decobruta Betts sp. nov., Kelanella sp., and Lapworthella fasciculata, spines of the bradoriid arthropod Mongolitubulus squamifer, and several problematica, such as Stoibostrombus crenulatus and a variety of tubular forms. The upper age limit for the WPC is constrained by biostratigraphic data from the overlying Marsden Sandstone and Emu Bay Shale, which are no younger than the Pararaia janeae Trilobite Zone (Cambrian Series 2, Stage 4). The shelly fossil assemblage from the WPC limestone clasts indicates an upper Dailyatia odyssei Zone (= Pararaia tatei to lower P. janeae trilobite zones), equivalent to the Atdabanian–early Botoman of the Siberian scheme. This contrasts with the previously suggested late Botoman age for the limestone clasts, based on the diverse archaeocyath assemblage. The minor age difference between the WPC and its fossiliferous limestone clasts suggests relatively rapid reworking of biohermal buildups during tectonically-active phases of deposition in the Stansbury Basin.

The enigmatic and aberrant lingulate brachiopod Aulonotreta antiquissima (Eichwald) from the Dapingian (Volkhov Stage) Toila Formation of northern Estonia and St Petersburg area (Historical Region of Ingria, Ingermanland, or Inkerinmaa; English, Swedish, Finnish) is re-described together with the new species, Aulonotreta neptuni, from the lower Darriwilian (Kunda Stage, lower Valastean Substage) Holen Limestone on the Island of Öland, southern Sweden. The genus is presently endemic to Baltoscandia. The new well-preserved material of Aulonotreta permits an account of the musculature, micro-ornamentation and siphonotretoid-like and non-baculate shell structure, all of which were previously poorly understood. The aberrant morphology and musculature of Aulonotreta suggest that it was adapted to an entirely epifaunal and most likely ambitopic adult mode of life.

A comprehensive review and phylogenetic analysis of genera and species presently assigned to the rhynchonelliform superfamily Nisusioidea and family Nisusiidae suggests that this short-lived but important group of brachiopods first appeared in peri-Gondwana during the second half of the Cambrian Series 2, before going extinct by the end of Drumian times. Nisusiides achieved their maximum morphological disparity and geographical distribution during the Wuliuan Age, and Laurentia was probably the major centre of their dispersal. A new phylogenetic analysis suggests an early separation of the lineages of spinose and non-spinose nisusiids. The non-spinose nisusiids probably evolved in Laurentia by the end of Cambrian Series 4. The new nisusiid genus Bellistrophia is described. The new species Nisusia multicostata represents the first documented rhynchonelliform (kutorginide) brachiopod from the Miaolingian (Drumian) of the Alborz Mountains, Iran.

A comprehensive review and phylogenetic analysis of genera and species presently assigned to the rhynchonelliform superfamily Nisusioidea and family Nisusiidae suggests that this short-lived but important group of brachiopods first appeared in peri-Gondwana during the second half of the Cambrian Series 2, before going extinct by the end of Drumian times. Nisusiides achieved their maximum morphological disparity and geographical distribution during the Wuliuan Age, and Laurentia was probably the major centre of their dispersal. A new phylogenetic analysis suggests an early separation of the lineages of spinose and non-spinose nisusiids. The non-spinose nisusiids probably evolved in Laurentia by the end of Cambrian Series 4. The new nisusiid genus Bellistrophia is described. The new species Nisusia multicostata represents the first documented rhynchonelliform (kutorginide) brachiopod from the Miaolingian (Drumian) of the Alborz Mountains, Iran.

The lower Cambrian (Series 2) White Point Conglomerate (WPC) on Kangaroo Island, South Australia contains exotic clasts representing a diverse array of lithologies, including metamorphics, chert, sandstone, and abundant carbonates, notably archaeocyath-rich bioclastic limestone. Acetic acid digestion of the WPC bioclastic limestone clasts reveals a diverse shelly fauna. This assemblage includes abundant organophosphatic brachiopods such as Cordatia erinae Brock and Claybourn gen. et sp. nov., Curdus pararaensis, Eodicellomus elkaniformiis, Eohadrotreta sp. cf. E. zhenbaensis, Eoobolus sp., Kyrshabaktella davidii, and Schizopholis yorkensis. Additional shelly taxa include the solenopleurid trilobite Trachoparia? sp., the tommotiids Dailyatia odyssei, Dailyatia decobruta Betts sp. nov., Kelanella sp., and Lapworthella fasciculata, spines of the bradoriid arthropod Mongolitubulus squamifer, and several problematica, such as Stoibostrombus crenulatus and a variety of tubular forms. The upper age limit for the WPC is constrained by biostratigraphic data from the overlying Marsden Sandstone and Emu Bay Shale, which are no younger than the Pararaia janeae Trilobite Zone (Cambrian Series 2, Stage 4). The shelly fossil assemblage from the WPC limestone clasts indicates an upper Dailyatia odyssei Zone (= Pararaia tatei to lower P. janeae trilobite zones), equivalent to the Atdabanian–early Botoman of the Siberian scheme. This contrasts with the previously suggested late Botoman age for the limestone clasts, based on the diverse archaeocyath assemblage. The minor age difference between the WPC and its fossiliferous limestone clasts suggests relatively rapid reworking of biohermal buildups during tectonically-active phases of deposition in the Stansbury Basin.

The enigmatic and aberrant lingulate brachiopod Aulonotreta antiquissima (Eichwald) from the Dapingian (Volkhov Stage) Toila Formation of northern Estonia and St Petersburg area (Historical Region of Ingria, Ingermanland, or Inkerinmaa; English, Swedish, Finnish) is re-described together with the new species, Aulonotreta neptuni, from the lower Darriwilian (Kunda Stage, lower Valastean Substage) Holen Limestone on the Island of Öland, southern Sweden. The genus is presently endemic to Baltoscandia. The new well-preserved material of Aulonotreta permits an account of the musculature, micro-ornamentation and siphonotretoid-like and non-baculate shell structure, all of which were previously poorly understood. The aberrant morphology and musculature of Aulonotreta suggest that it was adapted to an entirely epifaunal and most likely ambitopic adult mode of life.