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Within the genera of fossil Brachiopoda eight junior homonyms are found and the following replacement names are proposed: 1) Brachiotesuquea Ceccolini & Cianferoni nom. nov. = Tesuquea Sutherland and Harlow, 1973 nec Klots, 1936 (Insecta, Lepidoptera); 2) Brachiosvalbardia Ceccolini & Cianferoni nom. nov. = Svalbardia Barkhatova, 1970 nec Thor, 1930 (Acari, Oribatida); 3) Rhyncholeptospira Ceccolini & Cianferoni nom. nov. = Leptospira Boucot, Johnson & Staton, 1964 nec Swainson, 1840 (Gastropoda, Stylommatophora); 4) Rhynchogilviella Ceccolini & Cianferoni nom. nov. = Ogilviella Lenz, 1968 nec Paramonov, 1954 (Insecta, Diptera); 5) Spiriarchboldiella Ceccolini & Cianferoni nom. nov. = Archboldiella Winkler Prins, 2008 nec Heinrich, 1934 (Insecta, Hymenoptera); 6) Brachiokasakhstania Ceccolini and Cianferoni nom. nov. = Kasakhstania Besnossova, 1968 nec Arnol'di, 1960 (Insecta, Curculionidae); 7) Thecidanella Ceccolini & Cianferoni nom. nov. = Danella Pajaud, 1966 nec Gray, 1869 (Anthozoa, Alcyonacea); 8) Brachiobittnerella Ceccolini & Cianferoni nom. nov. = Bittnerella Dagys, 1974 nec Dall, 1898 (Bivalvia, Arcida). Moreover, 16 new combinations (comb. nov.) are made accordingly. [ABSTRACT FROM AUTHOR]

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A new collection of brachiopods made in 2003 from lower Pragian beds of the northeastern part of Heceta Island of Southeast Alaska allows us the opportunity to reevaluate some of the rhynchonellid and atrypid brachiopods that were previously described by Kirk & Amsden (1952) and Savage (1981) from the same locality. We here describe the following taxa: Kirkirhynchus gen. nov. with Ancillotoechia reesidei Kirk & Amsden, 1952 designated type species, Savagerhynchus hecetaensis gen. et sp. nov., Dubovikovia cf. kuzmini (Cherkesova, 1968) and Rugosatrypaflexibilis (Cherkesova in T. Modzalevskaya & Cherkesova, 1994). The occurrence of the two last species allows correlation of the lower Pragian beds of Heceta Island with Uryumskay, Tolbatskay and basal part of Daksanskay layers of Taimyr, Russia and the Soda Creek Limestone of west-central Alaska. Close faunal ties are clearly evidenced by Pragian brachiopod faunas of Southeast Alaska, southwest Alaska, Northeast Asia, and Taimyr. [ABSTRACT FROM AUTHOR]

Jacoburbirostrum gen. nov., type species Atrypa duplicata Hall, 1843, is described from the middle Famennian (II-G) of southwestern New York State, and a lectotype is formally designated. New family Jacoburbirostridae is established. [ABSTRACT FROM AUTHOR]

Paleobiogeographic patterns of the brachiopod faunas before and during the first radiation of the Great Ordovician Biodiversification Event (GOBE) in South China at 6 different localities from the upper Jiangnan Slope to the vast area of the Upper Yangtze Platform show several interesting features. First, the initial brachiopod diversity acme was accompanied by both high origination and extinction rates. Second, no significant changes took place in the taxonomic composition and paleobiogeographic pattern of the brachiopod fauna during the radiation at 5 of the 6 localities studied except the near shore locality, where the first brachiopod radiation was much later than at other localities and was marked by a dramatic increase in endemic constituents. Third, orthides were the predominant brachiopod group during the radiation, and regional brachiopod taxa played a significant role in defining the paleobiogeographic pattern of the radiation. Fourth, the first brachiopod radiation was associated with 3 major pulses of onshore migration from the upper Jiangnan Slope through the central Upper Yangtze Platform to the near shore settings of the platform, with the middle pulse being the most significant. Finally, paleogeographic dispersal took place in both onshore and offshore directions, although the onshore expansion was more prominent; several key brachiopods, such as Paralenorthis, Nocturnellia, Protoskenidioides, Nereidella, Euorthisina and Yangtzeella, first appeared on the upper Jiangnan Slope and later formed distinct, and taxonomically diverse, communities on the Upper Yangtze Platform. The paleogeographic dispersal of brachiopods is considered to be closely related to the tectonic evolution of the Qianzhong Arch. [ABSTRACT FROM AUTHOR]

The organophosphatic early Cambrian (Terreneuvian, Cambrian Stage 2) fossil Tumulduria incomperta has been problematic ever since its original description in 1969. Comparison of abundant specimens from the Lower Cambrian of Siberia with co-occurring brachiopod valves show that T. incomperta represents the central portion of the ventral interarea of a paterinid brachiopod similar to Cryptotreta neguertchenensis, and that the domed central portion of typical Tumulduria specimens represents the ridge-like pseudodeltidium of the interarea. [ABSTRACT FROM AUTHOR]

Immobile benthic organisms lacking attachment or cementation mechanisms are considered to be best adapted to quiet bottom environments. Since the free-living Lower Permian spiriferinide brachiopod Pachycyrtella omanensis inhabited a sandy substrate with high-energy water flow, flume experiments were performed to show the possible hydrodynamic advantages of shell morphology in postural stability and generation of feeding flows. Modelling indicates that a vertical position, with the commissure plane perpendicular to the seabed, was the most unstable, although it is considered to have been its original life position. On the other hand, the passive flow inside the model in vertical position exhibited vortex movement with constant degree of inhalent flow and exhalent flow, conferring advantages on the effective filtration of food particles using a spiral lophophore. The intensity and movement of the passive flow for feeding could have been adjusted through changes in the angle of opening of the valves. As the shoreface habitat was affected by oscillatory flows, a small-sized animal could have undergone a high risk of burial, while an increase in size would have led to easier removal from the sandy bottom. To avoid both physical risks, Pachycyrtella developed a thick shell with a high rate of growth, specifically increasing the weight of the ventral umbo without altering its morphofunction to generate passive feeding flows. Biomechanics, functional morphology, opportunistic species, Pachycyrtella, Spiriferinida, suspension feeder. [ABSTRACT FROM AUTHOR]

The upper Daguanshan Formation (middle Expansograptus hirundo graptolite biozone, Dapingian, early Middle Ordovician) of the Shuanghe area, Changning County, southern Sichuan Province, contains three new genera and species of strophomenoids: Ochyromena plana, Shuangheella elongata, and Primotimena globula, which are attributed to the Strophomenidae, Rafinesquinidae and Glyptomenidae respectively. These are the earliest known strophomenoids from the South China palaeoplate, and also the oldest rafinesquinid and glyptomenid brachiopods worldwide. Global review of the superfamily Strophomenoidea of Middle Ordovician age suggests that the first diversity peak at the species level occurred in late Darriwilian (Llanvirn) time, mainly as a result of the rapid diversification of the family Strophomenidae. The first appearance datum (FAD) of strophomenoids and their possible westward dispersal were from North China (latest Floian) and/or South China (early Dapingian), through the Chu-Ili terrane of Kazakhstan, Iran, and Baltica (early Darriwilian), to Avalonia and Laurentia (late Darriwilian). This points to the existence of early diversification hotspots of the strophomenoid superfamily in the North and South China palaeoplates during the early Middle Ordovician in generally shallow water (corresponding to BA2) environments. The high degree of similarity in the external morphology and ventral interior of the three new genera indicates that the early diversification of strophomenoids began with differentiation of the cardinalia, especially in the configuration of the bilobed cardinal process, a key evolutionary novelty for the strophomenoids. [ABSTRACT FROM AUTHOR]

Copyright of Comunicaçõe Geológicas is the property of Laboratorio Nacional de Energia e Geologia, I.P. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Spines are one of the most characteristic ornamenting features of many fossil brachiopod taxa. Despite several studies of spines in different species, there is still insufficient information about the development, functional morphology, and modifications of brachiopod spines. In particular, ontogenetic data are very rare and the understanding of the relationship between functional morphology and paleoecology is elusive. The present study analyzes the functional morphology and modifications on spines of the Pennsylvanian brachiopod species Heteralosia slocomi throughout ontogeny. Spines are tubular hollow and only displayed on the surface of the ventral valves, where they develop from a specific point at the margins of the growth lamellae and directed towards the antero-lateral margins. Modifications of up to 180 from this original direction of growth are observed in response to ecological pressure and biotic interactions. The function of these spines is primarily for attachment by clasping and cementation, but the possibility of spines acting as sensory mechanisms is not excluded. [ABSTRACT FROM AUTHOR]

In the sections of the West Uralian Folded Zone (western slope of the South Urals) the boundary between the Frasnian and Famennian (F/F) runs at the bottom of the Barma Horizon. It is established within a lithologically homogeneous brachiopod coquina by simultaneous appearance of the conodont Palmatolepis triangularis Sann. and brachiopod Parapugnax markovskii (Yud.). The brachiopod shell stone of the F/F boundary interval subdivided into the Upper rhenana, linguiformis, Lower-Middle triangularis zones are thoroughly characterized by means of conodonts. In the upper linguiformis Zone at the top of the Frasnian, all the sections show a replacement of the palmatolepid biof acies with its abundant taxa of the genus Palmatolepis by the extremely poor, practically monotaxon icriodid biofacies. This is probably due to changes in the global sea levels and the Mass Extinction Event (Upper Kellwasser Event) at the F/F boundary. [ABSTRACT FROM AUTHOR]

The acrotretideAcrotreta socialisvon Seebach, 1865 has suffered a long and tumultuous history since its original description from the middle Cambrian (Guzhangian Stage) Andrarum Limestone of Bornholm, Denmark. Uncertainties regarding key morphological characters have resulted in numerous revisions and redescriptions of the species with much of the taxonomic shuffling occurring before the mid-20thcentury. A major problem with the early documentation of acrotretide brachiopods is that many species were described in the days before the advent of the Scanning Electron Microscope (SEM), resulting in dubious interpretations of significant morphological characteristics, like the position of the pedicle foramen and the internal morphology of both valves. A detailed revision ofAcrotretaspecies resulted in the proposal that the genus is restricted solely to the Ordovician with the Bornholm acrotretide species subsequently left floating in taxonomic limbo. Recent taxonomic suggestions have been provisional, awaiting morphological information based on type or topotype material. The examination of topotype material in addition to supplementary material collected from southern Sweden has elucidated many of the previous ambiguous morphological characteristics of the species confirming that the original description was based on more than one brachiopod species. The new morphological information acquired here has resulted in the erection of a new acrotretid genus,Clupeafumosusgen. nov., to accommodate the material previously described asAcrotreta socialis. Co-occurring withClupeafumosus socialisin southern Sweden is another new acrotretide brachiopod,Monophthalma andersonisp. nov., which is additionally described. [ABSTRACT FROM AUTHOR]

The stratigraphy, brachiopod systematics and palaeoecology of the Upper Ordovician succession from the Cabrières Klippes, at the eastern ending of the southern slope of the Montagne Noire (southern France) are studied. Two new formations have been formally introduced: the Glauzy Formation (middle Katian, Ka2, in its uppermost fossiliferous strata) and the Gabian Formation (middle--upper Katian, Ka2--Ka4), to characterize, respectively, the thickly bedded quartzitic sandstones overlying volcaniclastic rocks, and the conformably overlying marls and limestones, rich in bryozoans, echinoderms and brachiopods. The systematic palaeontology of the brachiopods yielded in the uppermost beds of the Glauzy Formation has been studied, and five taxa are described, including a new platyorthid genus and species, Proclinorthis vailhanensis. The palaeoecological analysis of the Glauzy Fm., using both taphonomical and functional- morphological criteria, has allowed for the introduction of a new formal palaeoecological unit, the Svobodaina havliceki Community. It characterizes the recurrent low-diversity brachiopod association, usually dominated by S. havliceki, frequent in quartzitic sandstone lithofacies of the Upper Ordovician outcrops throughout southwestern Europe. It is interpreted as having developed in the shore face environments of the Benthic Assemblage 3 (BA-3), along the Gondwanan Mediterranean margin during the early- and mid-Katian. This new community is bounded coastward by an undescribed rhynchonellid community (BA-2) and seaward by the Nicolella Community (also BA-3), during its latest time span. This study allows a better understanding of when, why and how occurred the replacement of Gondwanan endemic associations, represented by the S. havliceki Community, by immigrant associations from low-latitude platforms, represented by the Nicolella Community, coinciding with the global warming Boda event. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Eospirifer, the oldest known genus of the spiriferide group (Brachiopoda), first appeared on the Zhe-Gan Platform of South China paleoplate during late Katian (Late Ordovician) represented by E. praecursor. It survived the end-Ordovician mass extinction, and reappeared on the Upper Yangtze Platform of South China paleoplate by the end of Ordovician near the upper part of the Normalograptus persculptus Biozone. Starting from the beginning of Silurian, Eospirifer experienced some morphological innovations and expanded its geographical distribution substantially. It reached its species diversity acme and the widest geographic distribution in Wenlock (middle Silurian), with the diversity hotspots in Laurentia, Avalonia, and Baltica. Various shell size frequency curves of E. praecursor under different paleogeographic settings suggest that this pioneer species of Eospirifer, with several macroevolutionary novelties, adopted a range of life strategies to adapt to the changing environments during early spiriferide evolution. There are also some morphological macroevolutionary trends during the evolutionary history of Eospirifer from Late Ordovician to the end of Silurian, such as the ever enlarging shell sizes and the width/length ratios from late Katian to Wenlock, but decreasing apparently of both parameters from Wenlock to Pridoli. [ABSTRACT FROM AUTHOR]

Copyright of Estonian Journal of Earth Sciences is the property of Teaduste Akadeemia Kirjastus and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Estonian Journal of Earth Sciences is the property of Teaduste Akadeemia Kirjastus and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Diverse carbonaceous microfossils, including exceptionally preserved remains of non-biomineralizing metazoans, are reported from a basal middle Cambrian interval of the Kaili Formation (Guizhou Province, China). The application of a gentle acid maceration technique complements previous palynological studies by revealing a larger size-class of acritarchs, a richer assemblage of filamentous microfossils, and a variety of previously unrecovered forms. Metazoan fossils include Wiwaxia sclerites and elements derived from biomineralizing taxa, including chancelloriids, brachiopods and hyolithids, in common with previously studied assemblages from the early and middle Cambrian of Canada. In addition, the Kaili Formation has yielded pterobranch remains and an assemblage of cuticle fragments representing "soft-bodied" worms, including a priapulid-like scalidophoran. Our results demonstrate the wide distribution and palaeobiological importance of microscopic "Burgess Shale-type" fossils, and provide insights into the limitations and potential of this largely untapped preservational mode. [ABSTRACT FROM AUTHOR]

The collection and study of benthic fauna from Middle Devonian carbonate buildups of the Maïder Basin in the eastern Anti-Atlas of Morocco permitted the taxonomic revision of previously described brachiopods from this area. Rhynchonellids dominate the brachiopod fauna. In this work, however, the focus is put on the description of a new gypidulid species, Ivdelinia pulchra, which belongs to the family Gypidulidae (subfamily Ivdelininae), found among the brachiopods from the Aferdou elMrakib reef mound. It represents the youngest Ivdelinia species so far described and is compared with other ivdelinids. Ivdelinia pulchra occurs as densely packed communities which lived in a carbonate pre-dominant environment during the earlier stage of reef mound growth, suggesting a more or less allochthonous state of these communities. However, this taxon does not properly belong to the reef guild. In addition we discuss the palaeoecology of the new species. [ABSTRACT FROM AUTHOR]

Typical elements of the Guanshan Biota are reported from the Cambrian Stage 4 Wulongqing Formation of Huize, Qujing, South China, approximately 100 km north of the Guanshan fossil sites previously reported. Lithostratigraphy and biostratigraphy of the current Zhujiaqing section are also discussed herein. Representatives of various phyla recovered therein include not only previously described sponges, palaeoscolecids, arthropods, brachiopods, echinoderms, and vetulicolians, but also some potential new taxa, e.g. a new species of Vetulicola. This new occurrence not only expands the palaeogeographic distribution of the Guanshan Biota, but also strengthens the ties between the younger Chengjiang Biota and the older Kaili Biota (and also the coeval Burgess Shale community). [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined brachiopod assemblages from Qingyan, Guizhou Province, China. Specimens of brachiopod were collected from the Qingyan Formation of Anisian. The total number of brachiopod species identified from 21 genera was 31, while seven assemblages were recognized. Results of the study showed that the Diholkorhynchia sinensis dominated the D assemblage. It also observed a stepwise diversification for the brachiopod faunas during the recovery/radiation time.

Jurassic rhynchonellide brachiopods from the Jordan Valley are herein revised and new taxa are added to the faunal list. In this study of Jurassic rhynchonellides from Wadi Zarqa, northwestern Jordan, we recognize the following taxa: Eurysites rotundus, Cymatorhynchia quadriplicata, Daghanirhynchia triangulata, D. angulocostata, Pycnoria magna, Schizoria elongata, and Schizoria cf. intermedia. The following new taxa are described: Daghanirhynchia susanae sp. nov. and Amydroptychus markowitzi sp. nov. The Middle Jurassic Mughanniyya Formation of northwest Jordan is dominated by limestone beds. The sedimentary environment is interpreted as neritic, light, and nutrient-rich resulting in high faunal diversity. The high rhynchonellide endemism of this fauna is yet another confirmation of pronounced Middle Jurassic endemism along the southern Tethyan margin of the Ethiopian Province. Brachiopods of the Jordanian Mughanniyya Formation can be correlated with the fauna of the Aroussiah Formation in Sinai and the Zohar and Matmor formations in Southern Israel. [ABSTRACT FROM AUTHOR]

Explaining the origin and maintenance of biodiversity is critical for understanding the potential consequences of present-day environmental change on ecological communities, as well as the evolutionary history of ecosystems in the Earth's past. Much effort in theoretical ecology has focused on identifying mechanisms that promote stable coexistence of species at equilibrium. However, in a consumer–resource model of competition along an environmental gradient, high-diversity assemblages have the potential to persist in non-equilibrium states for millions of generations with very little species loss. Species' populations in such competitively accommodated communities show slow drift; if disrupted, they rapidly reorganize into alternative persistent states. Fossil examples of prolonged ecological stability lasting 1–5 Myr punctuated by rapid reorganization (e.g. brachiopods from the Permian Reef of west Texas) suggest that some palaeocommunities represent a record of periodically disrupted transient states rather than stable equilibria. The similarity between the theoretical results reported here and palaeontological data suggests that the maintenance of high-diversity communities, both in the past and present, may reflect long-duration, non-equilibrium transient dynamics. If so, this has implications for the response of such communities to present-day environmental change, as well as for the evolution of lineages in such systems. [ABSTRACT FROM AUTHOR]

The most common forms of Late Ordovician dalmanellid brachiopods from the Cincinnatian type area, previously treated as either Dalmanella or Onniella, are assigned to Cincinnetina gen. nov. The new genus differs from Dalmanella and Onniella in having a consistently developed primary medial costa in the dorsal valve, a larger cardinal process that tends to develop a trilobed myophore, strongly differentiated fine and coarse punctae, and sparse aditicules. Cincinnetina can be distinguished from the closely related Paucicrura and Diceromyonia in its smaller trilobed cardinal process (when developed) that does not have a dominant medial lobe and does not extend into the delthyrial cavity of the ventral valve. Globally, Dalmanella and Onniella occur most commonly in deposits of relatively deep- or cool-water palaeoecological settings, whereas in North America, Cincinnetina, Paucicrura and Diceromyonia are found mainly in carbonate-rich deposits in warm-water depositional environments, with Cincinnetina and Paucicrura most common in pericratonic settings and Diceromyonia in palaeoequatorial inland seas. [ABSTRACT FROM AUTHOR]

Abstract: Early Cretaceous development of the Mecsek Mts. (South Hungary) is characterized by continental rifting that produced mixed volcano-sedimentary rocks in the Tihonian/Berriasian and built up a volcanic edifice in the earliest Cretaceous of ankaramite–alkaline basalts. During the Valanginian, marl sedimentation occurred in the basinal part containing rich pelagic fauna dominated by ammonites. Beside phylloceratids, lytoceratids and haploceratids, Kilianella roubaudiana, K. lucensis, Sarasinella eucyrta, Thurmanniceras pertransiens, Th. (Clavithurmannia) foraticostata, Busnardoites campylotoxus, Olcostephanus drumensis, O. densicostatus, and Sabbaiceras stefanescui are indicating the Early and Late Valanginian Thurmanniceras pertransiens, Busnardoites campylotoxus and Saynoceras verrucosum zones. The Early Valanginian is also supported by Calpionellites darderi indicating the calpionellid “E” zone. The marl sequence contains a turbidite bed with rich fauna of shallow marine origin from the volcanic slope of lagoonal, reef, and tidal environs, however it contains metasomatized limestone olistoliths of different origin. Source of these olistoliths is the near iron-ore deposit, which is considered an embryonic shallow water hydrothermal vent. It includes a remarkable fauna of rich crustacean coprolite ichnospecies of Favreina dispentochetarius, F. hexaochetarius, F. octoochetarius, Palaxius decaochetarius, P. tetraochetarius, P. triochetarius. In the neighbourhood of the embryonic vent, a remarkable megafauna occurs, which is an almost monospecific brachiopod fauna dominated by Lacunosella hoheneggeri. Other brachiopods as Nucleata veronica, Moutonithyris moutoniana, Karadagithyris sp., and Zittelina pinguicula also occur as stray individuals. Together with benthic megafauna, nektonic elements as Nautiloidea gen. et sp. ind, phylloceratid- and lytoceratid ammonites and echinoid spines of Balanocidaris rysacantha occur. [Copyright &y& Elsevier]

An unusual fossil assemblage dominated by superabundant rhynchonellid brachiopods in a stromatactis mud-mound is recorded from the Hăghimaş Mountains (Eastern Carpathians), Romania. The mound mainly consists of bioclastic wackestones to packstones with a very rich macrofauna including crinoids, sponges, juvenile ammonites, and echinoids. The brachiopods represent a low-diversity but high-abundance association, dominated by the rhynchonellids Lacunosella and Septaliphoria. The taphonomical features of the fossil assemblage indicate an autochthonous fauna, with successive generations of brachiopods in life position and complete well-preserved individuals in different growth stage alongside an accessory population of crinoids and sponges. Brachiopod-brachiopod endosymbiotic life strategy is documented for the first time from a post-Paleozoic brachiopod assemblage. The mound reveals abundant stromatactis, filled by radiaxial fibrous or drusy calcite cement and internal polymud sediments. This is the first Late Jurassic (Kimmeridgian) stromatactis mud-mound identified in the Eastern Carpathians. [ABSTRACT FROM AUTHOR]

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With the definition and adoption of the Global Stratotype Section and Point (GSSP) for base of the Visean in China, the newly synthesized zonations and correlation of some significant fossil groups: foraminifera, conodont, coral and brachiopoda near the Tournaisian-Visean boundary beds are reviewed, which help in the recognition of the boundary in various sedimentary facies. The occurrence of two physical events, one pre- and one post- the Tournaisian-Visean boundary is emphasized, which allows for recognition of the position close to the Tournaisian-Visean boundary in the field. The regional correlation in southern China and international correlation throughout Eurasia around the Tournaisian-Visean boundary beds with the GSSP is proposed. [ABSTRACT FROM AUTHOR]

Brachiopods are marine Lophotrochozoa whose soft parts are enclosed in a bivalved shell. Although brachiopods are represented by a rich record from the Early Cambrian to the present, the origin of their bivalved body plan remains controversial. The Early Cambrian organophosphatic tommotiids Micrina and Paterimitra from Australia have been proposed as stem brachiopods. Here, we describe their earliest ontogeny, indicating that tommotiids possessed bivalved planktotrophic larvae. The curious combinations of characters in Micrina and Paterimitra indicate that they may belong to the stems of the Linguliformea and Rhynchonelliformea, respectively. The bivalved shell of adult living brachiopods may represent a plesiomorphic character retained from planktic tommotiid larvae; the crown group body plan of the Brachiopoda may have evolved through the paedomorphic retention of a bivalved larval state. [ABSTRACT FROM AUTHOR]

Ordovician strophomenoidean and plectambonitoidean brachiopods are reviewed and partially redescribed from the Caradoc (Sandbian to Early Katian) age rocks of Wales and the Welsh Borderland of England, then forming part of the Avalonia Terrane. There are 51 nominal species available, of which 12 are synonymised here and many transferred to different genera. Strophomenoids occurred sporadically, often rarely but occasionally abundantly, particularly in mid-shelf benthic assemblages, and 21 named species and subspecies are noted, including the new Kiaeromena ( Kiaeromena) harperi, as well as six in open nomenclature. The common genus Kjaerina, with six species known from the area, is revised in detail. In contrast to the strophomenoids, plectambonitoids were more common in shallow and mid-shelf assemblages, including Eoplectodonta ( Eoplectodonta) abigailae sp. nov., with Sowerbyella in particular dominating many bedding planes, and 17 named species are reviewed, as well as three in open nomenclature. The distinctive Gunningblandella, hitherto known only from Australia and Kazakhstan, is recorded for the first time from Europe. The Avalonian strophomenides are compared with those from neighbouring terranes, particularly Laurentia and Baltica, during a time when the seas between those terranes were narrowing, and the faunas from the three terranes are found to be largely similar at the generic level, although there are few species in common. In contrast, there are few genera in common between those three terranes and the Mediterranean Province of Northwestern Gondwana. [ABSTRACT FROM AUTHOR]

The marine upper Darriwilian (Middle Ordovician) Elnes Formation of southern Norway contains very rich and diverse invertebrate faunas. Stratigraphically detailed recent collections of these well-preserved faunas have permitted a more thorough description of the various faunal groups and their preferences in the late Middle Ordovician of the Oslo Region, southern Norway, than ever before. The brachiopod faunas are described in the present article, which include a new genus and a new species respectively Wandaasella modheimrensis and Cyclomyonia vikersundi. The brachiopod fauna is largely dominated by linguliformeans although some sections of the formation are dominated by the plectambonitoids Alwynella ildjernensis Spjeldnæs or Cathrynia aequistriata (Hadding) or by orthid brachiopods. Statistical analysis of the brachiopod fauna reveals that the general depositional trend of the Elnes Formation is that of a regressive event from the lower part of the Sjøstrand Member to the Håkavik Member. Three main brachiopod associations are recognised: a deep-water, lingulid dominated association associated with quiet and dysoxic bottom conditions, a sowerbyellid dominated association (e.g. Cathrynia and Alwynella) found in muddy to marly deposits formed around maximal storm wave base and an orthid-dominated association representing an environment characterised by a fairly coarse or hard bottom substrate formed well above storm wave base but below fair weather wave base. [ABSTRACT FROM AUTHOR]

The classic Chengjiang Lagerstätte (Lower Cambrian, Atdabanian stage: Yu'anshan Formation) Yunnan, southwestern China, has yielded, besides the exceptional and often controversial soft-bodied fossils, a fauna of primitive/early lingulid brachiopods. Diandongia pista (Rong 1974) is one of the commonest and most strongly mineralized of the phosphatic brachiopods from the Lagerstätte. The shells of this species have been found to commonly serve as a basibiont host. Epibionts comprise the coeval brachiopod Longtancunella chengjiangensis and the cone-shaped cnidarian-related Archotuba conoidalis, as well as rounded smaller-sized epizoans (lesser than 2 mm). A principle morphological analysis demonstrates that the ovoid and rounded organisms that often occur along the commissure of D. pista resemble small juvenile or immature brachiopods. Epibiont-bearing shells of D. pista with soft-tissue preservation demonstrate that the host brachiopods were overgrown while alive, and provide an argument for D. pista having a semi-infaunal life style with only the slim pedicle embedded in sediment. The epibiotic association sheds direct light on the ecology of Cambrian brachiopods in soft-substrate marine environments. The Chengjiang fossils demonstrate that the Early Cambrian brachiopods, as compared with recent lingulids, occupied different and a wider spectrum of ecological niches and tiers of space. [ABSTRACT FROM AUTHOR]

The Ocruranus– Eohalobia group, whose members were variously considered to be brachiopods, bivalves, chitons, tommotiids and coeloscleritophorans, are difficult to classify because of lack of morphological detail and evidence for skeletal reconstruction. New specimens from South China reveal more information about Ocruranus– Eohalobia and allow progress towards deciphering the skeletal reconstruction and phylogenetic affinity of this enigmatic group. Many specimens have a phosphatic inner and outer coat (mould) with empty space in between that resulted from dissolution of the original shell. Moreover, many of the internal moulds show a previously unknown type of shell microstructure that consisted of stacked layers of highly organized, acicular crystallites that radiated from the apex of the shell towards the aperture. The dissolved shell and needle-like crystals suggest an original calcareous, probably aragonitic, shell mineralogy. A few specimens also show a polygonal texture in regions that suggests the shell had a thin, prismatic inner shell microstructure. Ocruranus and Eohalobia belong to the same skeleton, and we herein synonymize Eohalobia with the older Ocruranus. Moreover, new specimens from Meishucun reveal a third type of shell plate, similar in form and inferred placement to intermediate valves of chitons. Ocruranus is likely a mollusc, and possibly a member of the chiton stem lineage. If so, then the beginning of the known record of chitons would be extended back from late Cambrian ( Saukia Zone; Furongian) to early Cambrian (Meishucunian; Series 1). [ABSTRACT FROM AUTHOR]

The origin of the latitudinal diversity gradient remains one of the most significant, unresolved challenges in macroecology, yet it has received relatively little attention from paleontologists. A new database of brachiopod genus occurrences in space and time has been used to reconstruct the latitudinal diversity gradient from 530 million years ago to the present day in 10-million-year increments. A latitudinal diversity gradient has persisted continuously through time. Notably, peak diversity did not usually occur at or near the equator but drifted northward through time, beginning in southern midlatitudes in the early Paleozoic Era and culminating in northern midlatitudes today. This pattern remains even after various corrections for sampling bias. The shift in peak diversity closely parallels a concomitant shift in the latitudinal distribution of continental shelf area, suggesting that shelf area has exerted a strong control of first-order spatial patterns of brachiopod diversity. The steepness of the gradient was controlled by the rise and fall of peak diversity, which was temporally more variable than diversity at higher latitudes. These results demonstrate the continuous presence of a latitudinal diversity gradient of brachiopod genera through most of the Phanerozoic, despite major changes in the global diversity and ecological dominance of the brachiopods. [ABSTRACT FROM AUTHOR]

Background: Carboxysomes are polyhedral protein microcompartments found in many autotrophic bacteria; they encapsulate the CO2 fixing enzyme, ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) within a thin protein shell and provide an environment that enhances the catalytic capabilities of the enzyme. Two types of shell protein constituents are common to carboxysomes and related microcompartments of heterotrophic bacteria, and the genes for these proteins are found in a large variety of bacteria. Methodology/Principal Findings: We have created a Halothiobacillus neapolitanus knockout mutant that does not produce the two paralogous CsoS4 proteins thought to occupy the vertices of the icosahedral carboxysomes and related microcompartments. Biochemical and ultrastructural analyses indicated that the mutant predominantly forms carboxysomes of normal appearance, in addition to some elongated microcompartments. Despite their normal shape, purified mutant carboxysomes are functionally impaired, although the activities of the encapsulated enzymes are not negatively affected. Conclusions/Significance: In the absence of the CsoS4 proteins the carboxysome shell loses its limited permeability to CO2 and is no longer able to provide the catalytic advantage RubisCO derives from microcompartmentalization. This study presents direct evidence that the diffusion barrier property of the carboxysome shell contributes significantly to the biological function of the carboxysome. [ABSTRACT FROM AUTHOR]

A brachiopod fauna from the uppermost part of the Tournaisian Tournai Formation (Belgium) contains an undetermined species of Crurithyris (Spiriferida, Ambocoeliidae), which displays numerous bored shells. About 8% of the 432 specimens with conjoined valves display single, small (≤ 1 mm) boreholes, which are smooth-sided, cylindrical or weakly conical, circular to slightly elliptical in plan view, perpendicular to the shell surface and generally complete. Of the 35 bored articulated specimens, 27 were drilled on the ventral valve. Most of the boreholes are located in the posterior half of the shell, and no case of edge-drilling has been observed. The boreholes were drilled by a predator, or possibly a parasite, which selected individuals greater than 2.5 mm long. Crurithyris sp. may have represented an attractive (in terms of energy cost) and easy target for a small-sized predator because of its thin shell and ornament of minute spines. [ABSTRACT FROM AUTHOR]

Dead-live faunal comparisons can offer powerful data to detect natural or human-induced population changes in the late Holocene. Here, we document dead-live comparisons for death assemblages of the brachiopod Bouchardia rosea in nearshore (0-45 m) environments along the northern coast of Sao Paulo State, Brazil. The sampling programme included 30 stations (14 at Ubatuba, 16 at Picinguaba bay). The bottom was sampled via Van Veen grab sampler, and also dredged. Out of 30 stations, 22 yielded brachiopods. The fidelity estimates were obtained by direct comparisons of live biota with dead shells. A total of 6627 brachiopods were recovered, 5339 (80.6%) from Ubatuba and 1288 (19.4%) from Picinguaba. Out of these, 6621 (99.9%) were empty, dead shells, while only six individuals (0.1%) were found alive, all in the Picinguaba Bay. These results suggest extremely poor dead-live compositional fidelity for B. rosea assemblages. The spatial data suggest that the distribution of B. rosea accumulations has been highly patchy in the region, whereas the great scarcity of live brachiopods may point to a recent decline in local populations. Several lines of evidences indicate that changes in water temperature, nutrient availability, population history and even pollution, may have all affected spatio-temporal dynamics of B. rosea populations. [ABSTRACT FROM AUTHOR]

Early Cambrian tommotiids are problematic fossil metazoans with external organophosphatic sclerites that have been considered to be basal members of the lophophorate stem group. Tommotiids are almost exclusively known from isolated or rarely fused individual sclerites, which made previous reconstructions of the actual organism highly conjectural. However, the recent discovery of the first articulated specimens of the tommotiid Eccentrotheca revealed a tubular sclerite arrangement (scleritome) that limited the possible life habit to sessile filter feeding and thus further supported a lophophorate affinity. Here, we report the first articulated specimens of a second tommotiid taxon, Paterimitra from the Early Cambrian of the Arrowie Basin, South Australia. Articulated specimens of Paterimitra are composed of two bilaterally symmetrical sclerite types and an unresolved number of small, asymmetrical and irregular crescent-shaped sclerites that attached to the anterior margin of the symmetrical sclerites. Together, the sclerites form an open cone in which the symmetrical sclerites are joined together and form a small posterior opening near the base of the scleritome, while the irregular crescent-shaped sclerites defined a broad anterior opening. The coniform scleritome of Paterimitra is interpreted to have attached to hard substrates via a pedicle that emerged through the small posterior opening (sometimes forming a tube) and was probably a sessile filter feeder. The scleritome of Paterimitra can be derived from the tubular scleritome of Eccentrotheca by modification of basal sclerites and reduction in tube height, and probably represents a more derived member of the brachiopod stem group with the paired symmetrical sclerites possibly homologous to brachiopod valves. [ABSTRACT FROM AUTHOR]

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New material of the enigmatic brachiopod Salanygolina obliqua Ushatinskaya from the Early Cambrian of Mongolia shows that it has a colleplax– a triangular plate – in the umbonal perforation, which is enlarged by resorption. This structure is otherwise only known from the equally enigmatic Palaeozoic orders Chileida and Dictyonellida (Rhynchonelliformea, Chileata). The colleplax in Salanygolina is here considered to be homologous with that of the chileates. Salanygolina is also provided with a ridge-like pseudodeltidium, which is another chileate feature. Other characters of Salanygolina, like the radial arrangement of adductor muscle scars and postero-medially placed internal oblique muscles are characteristic of chileates, but also found in the paterinates. In contrast, mixoperipheral dorsal valves with low rudimentary interareas are well known in paterinates, but not yet recorded from chileates. Thus, Salanygolina shows a mosaic combination of morphologic characters, known both from the paterinates and chileates, indicating that it may represent a stem group of the rhynchonelliform chileate brachiopods. The laminar phosphatic secondary shell of Salanygolina is composed of closely packed and nearly identical hexagonal prisms, oriented with their long axis normal to the laminae in a honeycomb pattern. The prism walls appear to have originally been composed of organic membranes and might represent precursors of the organic sheaths of calcite fibers that are typical of calcitic shells with a fibrous microstructure. [ABSTRACT FROM AUTHOR]

The eastern Alborz Mountains of Iran comprise a significant peri-Gondwanan terrane relevant to the early evolution of late Cambrian – early Ordovician brachiopods incorporated into the emerging benthic biota of the Paleozoic Evolutionary Fauna. A low diversity brachiopod assemblage from the late Tremadocian unit of the Lashkarak Formation contains six new species including the polytoechioideans Polytoechia and Protambonites and the orthoideans Paralenorthis, Ranorthis, Tarfaya and Xianorthis. The fauna preserves the earliest records of Polytoechia, unknown previously outside Laurentia and the Uralian margin of Baltica, and of Paralenorthis and Ranorthis, which were widespread along Gondwanan margins and in Baltica from the Floian (Arenig), plus Xianorthis, known hitherto only from the Floian of South China. The enigmatic Tarfaya has an impunctate shell fabric and setigerous perforations along the posterior margin, indicating placement within the Orthoidea in a new Family Tarfayidae. New species of Polytoechia, Protambonites, Paralenorthis, Ranorthis, Tarfaya, Xianorthis are described. [ABSTRACT FROM AUTHOR]

Many articulated brachiopods experience marked life habit variations during ontogeny because they experience their fluid environment at successively higher Reynolds numbers, and they can change the configuration of their inhalant and exhalant flows as body size increases. We show that the extant brachiopod Terebratalia transversa undergoes a substantial ontogenetic change in reorientation governed by rotation around the pedicle. T. transversa′s reorientation angle (maximum ability to rotate on the pedicle) decreases during ontogeny, from 180 degrees in juveniles to 10–20 degrees in individuals exceeding 5 mm, to complete cessation of rotation in individuals larger than 10 mm. Rotation ability is substantially reduced after T. transversa achieves the adult lophophore configuration and preferred orientation with respect to ambient water currents at a length of 2.5–5 mm. We hypothesize that the rotation angle of T. transversa is determined mainly by the position of ventral and dorsal points of attachment of dorsal pedicle muscles relative to the pedicle. T. transversa shows a close correlation between the ontogenetic change in reorientation angle and ontogeny of morphological traits that are related to points of attachment of dorsal pedicle muscles, although other morphological features can also limit rotation in the adult stage. The major morphological change in cardinalia shape and the observed reduction of rotation affect individuals 2.5–10 mm in length. The position of ventral insertions of dorsal pedicle muscles remains constant, but contraction of dorsal pedicle muscles is functionally handicapped because dorsal insertions shift away from the valve midline, rise above the dorsal valve floor, and become limited by a wide cardinal process early in ontogeny (<5 mm). The rate of increase of cardinal process width and of distance between dorsal pedicle muscle scars substantially decreases in the subadult stage (5–10 mm), and most of the cardinalia shell traits grow nearly isometrically in the adult stage (>10 mm). T. transversa attains smaller shell length in crevices than on exposed substrates. The proportion of small-sized individuals and population density is lower on exposed substrates than in crevices, indicating higher juvenile mortality on substrates prone to grazing and physical disturbance. The loss of reorientation ability can be a consequence of morphological changes that strengthen substrate attachment and maximize protection against biotic or physical disturbance (1) by minimizing torques around the pedicle axis and/or (2) by shifting energy investments into attachment strength at the expense of the cost involved in reorientation. [ABSTRACT FROM AUTHOR]

A characteristic etching trace, comparable to those produced by pedicles of some Recent brachiopods, was found on a Late Cretaceous, Campanian oyster shell from a mangrove-like setting in the Åsen quarry, Sweden. The trace fossil belongs to the ichnospecies Podichnus centrifugalis Bromley & Surlyk, 1973 and is, together with a single specimen of Crania craniolaris Linnæus, 1758, the only evidence of brachiopods in the mangrove-like environment. [ABSTRACT FROM AUTHOR]

The fossil record of drill holes in marine invertebrates has received a considerable amount of interest from paleontologists, primarily due to its importance for reconstructing the history of interactions between drilling predators and their prey. Such drill holes have been described in numerous studies of Paleozoic brachiopods but rarely in those focusing on brachiopods of the post-Paleozoic, a striking pattern given that in the late Mesozoic and Cainozoic drilling gastropods diversified and frequencies of drilled molluscs increased dramatically. During the past several years, however, drilled brachiopods were reported in several studies of the Mesozoic and Cainozoic, suggesting that this phenomenon may be more common than has been previously assumed. Here we report on 10 genera of brachiopods from four Cainozoic basins in Australia of which 7 shows evidence of having been drilled by predators. Of 298 specimens examined, 38 contain a single complete hole. Drilled specimens were identified in all 4 basins and in all stratigraphic units. When considered in the context of recent reports of drilled Cainozoic brachiopods, these Australian brachiopods further imply that drilling predation on these invertebrates was geographically, taxonomically and temporally widespread. [ABSTRACT FROM AUTHOR]

A new terebratulid brachiopod species, Rhenorensselaeria jansenii, has been identified in the Merzâ-Akhsaï Formation of the Dra Valley, Morocco, and the Grauwacke de Montguyon of the Amorican Massif, France. It is compared with the other known species of Rhenorensselaeria from Europe, Rh. strigiceps and Rh. demerathia, as well as with Rh. macgerriglei from North America, from which it differs in being larger and having coarser costae. Its possible life habit in clusters and its fossil community are compared with those of Rh. strigiceps from the Rheinisches Schiefergebirge (‘Rhenish Slate Mountains’), Germany, which it most resembles. A new phylogeny of the subfamily Rhenorensselaerinae is constructed. The close phylogenetic relationship between Rh. jansenii and Rh. strigiceps confirms close palaeobiogeographical relationships between North Africa, France and the Rheinisches Schiefergebirge as well as a wider relationship between Central Europe and Gaspé, eastern Canada, during the Early Devonian. Taxa of Rhenorensselaeria are mainly restricted to the Middle and Upper Siegenian, although rare individuals have been found in the Lower Emsian of Central Europe and North America. Because of their abundance in the Dra Valley and Rheinisches Schiefergebirge and their short life span, rhenorensselaerid taxa can be regarded as important stratigraphical markers of Middle–Late Siegenian and Early Emsian sediments in North Africa and Central Europe. [ABSTRACT FROM AUTHOR]

Studies of ecosystem level changes in the geological record have found that the major extinction events eliminated many incumbent clades that had been ecologically dominant for long intervals. Surviving clades that had not been able to compete with the extinct incumbents were then able to evolve adaptations that allowed them to move into the niches vacated by the incumbents. Underlying this pattern is the inability of clades that do not occupy a particular niche to evolve adaptations that would permit them to compete with incumbent clades that are already successfully occupying that niche. The zoogeographic distributions of brachiopods in the Late Ordovician of Laurentia may also have been maintained by incumbency, which was disrupted by the end-Ordovician extinction event. Following the extinction event, an Early Silurian zoogeographic reorganization occurred, during which surviving clades evolved into the vacated epeiric sea niches in the Early Silurian. Just as incumbency plays a role in long-term evolutionary patterns, zoogeographic realms and provinces are also partially maintained by incumbency. [ABSTRACT FROM AUTHOR]

The average body size of brachiopods from a single habitat type increased gradually by more than two orders of magnitude during their initial Cambrian-Devonian radiation. This increase occurred nearly in parallel across all major brachiopod clades (classes and orders) and is consistent with Cope's rule: the tendency for size to increase over geological time. The increase is not observed within small, constituent clades (represented here by families), which underwent random, unbiased size changes. This scale-dependence is caused by the preferential origination of new families possessing initially larger body sizes. However, this increased family body size does not confer advantages in terms of greater geological duration or genus richness over families possessing smaller body sizes. We suggest that the combination of size-biased origination of families and parallel size increases among major, more inclusive brachiopod clades from a single habitat type is best explained by long-term, secular environmental changes during the Paleozoic that provided opportunities for body size increases associated with major morphological evolution. [ABSTRACT FROM AUTHOR]

Characterization of the nature and distribution of organic components is crucial to understand shell formation in marine invertebrates. Although several techniques can provide detailed information at high spatial resolution, few of them are non-destructive and informative in a larger structural context. We explore the use of confocal laser scanning microscopy (CLSM) to obtain a better understanding of the distribution of organic components in calcitic shells of brachiopods focusing on perforations (punctae) across the shell. Resulting intensities and patterns of fluorescence correspond well with the distribution of polysaccharides and proteins as reported in previous histological and biochemical studies. Confocal laser microscopy is, therefore, a useful tool to be combined with other techniques to improve our knowledge of biomineral structures in marine invertebrates. [ABSTRACT FROM AUTHOR]