REVIEW OF UPPERMOST FURONGIAN TRILOBITES FROM SCANIA, SOUTHERN SWEDEN, BASED ON TYPE MATERIAL

Abstract:  The Scandinavian trilobites described in the classical papers by Moberg and Möller (1898) and Moberg (1898) are reviewed, based on the original type collections. The ten species and subspecies originally described are here considered to represent 12 species and subspecies, ranging in age from the latest Furongian (late Cambrian) through the Tremadocian (Early Ordovician). Lectotypes are selected for Parabolina ( Parabolina ) acanthura (Angelin), Acerocare ecorne Angelin and Westergaardia lata (Matthew). Leptoplastus claudicans (Moberg and Möller) is regarded as a junior subjective synonym of L . stenotus Angelin. These, and lectotypes formerly only figured by hand-drawings, are illustrated by high-resolution photographs.     

Structure, ontogeny, and moulting of the olenid trilobite Ctenopyge (Eoctenopyge) angusta Westergård, 1922 from the upper Cambrian of Västergötland, Sweden

The genus Ctenopyge is known mainly from disarticulated sclerites and from rare complete specimens flattened in shales. Hitherto, very few specimens have been found preserved intact and in three dimensions. In a recently discovered fauna, however, in the Peltura minor Subzone in Västergötland, central Sweden, there occur several species of Ctenopyge , of which many are complete and superbly preserved; moreover they occur at all stages of growth. Of these the abundant Ctenopyge ( Eoctenopyge ) angusta Westergård, 1922 is described and reconstructed here as an adult, and the entire ontogeny is documented for all post–protaspid growth stages. Many characters typical of the adult, such as the long genal spines and the caudal spine, develop very early in ontogeny, and the relative dimensions of the cranidium do not greatly change during growth. Macropleural spines, however, develop later. The transitory pygidium, relatively large and shield–shaped in the early meraspid, later becomes very small as the ten thoracic segments are liberated; a median spine develops on the last thoracic segment only at the holaspid stage. Instar groupings can be clearly distinguished for the early stages. Recurrent associations of sclerites are interpreted as moulting configurations. As reconstructed, the genal spines are horizontal and parallel with the extended thorax; an adaptation which presumably allowed the trilobite to rest on the sea floor.     

Partial regeneration of a genal spine by the trilobite Ceraurus plattinensis

A slender extension of a rounded stump on the proximal portion of the left genal spine of Ceraurus plattinensis Foerste, 1920 from the Middle Ordovician of Ontario, Canada records the partial regeneration of a genal spine. The regenerated spine possesses almost normal prosopon of fine granules and resembles the distal portion of the normal right genal spine. It demonstrates the following aspects about this trilobite's physiology: partial regeneration of genal spines could take place even if severed proximally. partial regeneration of genal spines could take place even in late holaspid individuals and the pattern of regeneration took place in a distoproximal order.     

A complete styginid trilobite from the Ordovician of Sweden

Styginidae are a small group of trilobite species, which are usually rare and most of which are incompletely known. Here we describe a complete specimen of Raymondaspis grandigena n.sp. from the Middle Ordovician (Darriwilian, upper Arenig) of Sweden. Among the group it has an unusual combination of exceptionally large genal spines, a thorax with notably short pleural spines in the anterior tergites, and a wide concave pygidial margin. The hypostome is documented for the first time in situ in a styginid, and its attachment can be best described as semi-impendent.     

A reconstruction of Telephina bicuspis, a pelagic trilobite from the Middle Ordovician of the Oslo Region, Norway

Well preserved parts of Telephina bicuspis described from dark limestone concretions of Llanvirn age, in the Oslo Region, Norway, exhibit many features associated with a pelagic life style for this trilobite. The free cheek has a huge holochroal eye with perfectly square lenses and a long genal spine which is unique in being directed vertically upwards rather than ventrally. Additional spines include an occipital spine, the macro spine on the rachis of the 6th thoracic segment and paired spines from each of the two rachial rings of the pygidium. These spines may have had a hydrodynamic and stabilizing function. The genal spine could have had a sensory function or been a dimorphic feature. The hypostoma is figured for the first time and a reconstruction is given for the complete exoskeleton.     

A new species and a new record of Nycteridopsylla Oudemans, 1906 (Siphonaptera: Ischnopsyllidae) from China

A new species, Nycteridopsylla quadrispina, found on the vespertilionid bat Ia io, is described from China. N. iae Beaucournu & Kock, 1992, a new record for China, was also found on the same host. The new species is distinguished by the presence of four spines on the genal comb and by the shape and chaetotaxy of the head.     

The Natural History of a Nearctic Temporary Pond in Ontario with Remarks on Continental Variation in such Habitats

The seasonal succession of members of the invertebrate community of a temporary vernal pond in southern Ontario is described. Although succession was essentially continuous, 5 faunal groups are suggested, based on time of appearance and duration of active forms in the pond. Some species were found during virtually the entire aquatic phase, while others completed their life cycles in only 2-3 weeks. Analysis of growth rates revealed many different patterns between species and groups. Analysis of community structure in terms of trophic status indicated shifts which coincided with the seasonal occurrence of the pond's potential food resources. Comparison of this fauna with that of a similar pond on Vancouver Island, British Columbia (some 2,400 km to the west) showed many similarities in niche occupancy, including 6 species in common. The biological characteristics leading to the success of these cosmopolitan species in temporary aquatic habitats is discussed.     

Geopalaeontological setting,chronology and palaeoenvironmental evolution of the Baccinello-Cinigiano Basin continental successions (Late Miocene,Italy)

The Latest Miocene succession of the Baccinello-Cinigiano Basin in southern Tuscany (Italy) recorded a faunal turnover documenting the extinction of an older, insular, endemic faunal complex characterised by the extinct ape Oreopithecus bambolii and the setting of a new, continental, European faunal complex including the colobine monkey Mesopithecus. A similar turnover pattern (Late Miocene ape/Latest Miocene Cercopithecidae) is generally observed in Late Miocene continental successions of Eurasia, from Spain to central Europe, Southwest Europe, the near East, and Southwest Asia. Abundant literature reports that the Late Miocene Eurasian hominoid primate distribution closely tracks the climatic/environmental changes occurring during the 12–9 Ma interval, until their extinction in western Europe. In the primate record, the dispersion of Cercopithecidae and the contraction of hominids is interpreted as an event depicting a pattern of “continentalisation” in the Old World. The sedimentary succession of the Baccinello-Cinigiano basin, one of the longest continuous vertebrate-bearing continental successions in the Neogene Italian record, contributes to the debate on this hypothesis. This paper provides an overview of the main characteristics of the sedimentary succession, the chronological constraints (biochronology, radiometric datings, magnetostratigraphy), and the palaeoenvironmental evolution as derived from palaeobiological approaches and from the study of stable carbon and oxygen isotope contents along the entire sedimentary succession. The 2 myr geological history of the Baccinello Cinigiano Basin, which documents the evolutionary history of Oreopithecus and associated faunas, does not have a direct relation with the event of the Messinian Salinity Crisis. The evolutionary history of Baccinello-Cinigiano Basin and its palaeontological record have been mainly driven by the regional tectonism and palaeogeographic changes that affected the northern Tyrrhenian regions in Late Miocene (Latest Tortonian–Messinian) times.     

L’assemblage à Cardioceras (Cardioceras) cordatum (J. Sowerby, 1812) et sa place au sein de la succession ammonitique de l’Oxfordien Inférieur (Jurassique Supérieur). Apport des données ardennaises (Province Subboréale)

Some temporary outcrops at Villers-le-Tourneur/Neuvizy (Ardennes, France), made possible the observation and biostratigraphical dating of Uppermost Callovian to Early Middle Oxfordian poorly known formations. Especially, the “Oolite Ferrugineuse de Villers-le-Tourneur–Neuvizy” is a quite thick marly unit, yielding some silicified fossils well known since the XIX^th century. With details, the Formation displays the succession of several faunal associations, characterizing the main subzones of the Cordatum Zone (Late Lower Oxfordian) and the Plicatilis Zone (Early Middle Oxfordian). Amongst many other species, Cardioceras cordatum (Sowerby, 1812) corresponds to a rare taxon or morphotype, yielded by the bottom part of the Formation. Then, the ultimate Lower Oxfordian faunal association is dominated by ammonites related to C. persecans. These Early Oxfordian are widely dominated by the family Cardioceratidae, commonly associated with Aspidoceratidae; such a structure is related to the “subboreal associations”, typically represented in Great Britain. Immediately after the Middle Oxfordian boundary, some “subtethysian” ammonites (mainly Perisphinctidae), occur in a larger number without being dominant, that emphasizing the northern location of the Ardennes margin. Then locally, two faunal associations succeed, which are characterized by C. cordatiforme (with Euaspidoceras perarmatum), and C. densiplicatum, respectively. Both are typical associations of the Vertebrale Subzone (Early Middle Oxfordian).     

Post-embryonic development of the Furongian (late Cambrian) trilobite Tsinania canens: implications for life mode and phylogeny

SUMMARY The current concept of the order Asaphida was proposed to accommodate some Cambrian and Ordovician trilobite clades that are characterized by the possession of a ventral median suture. The family Tsinaniidae was recently suggested to be a member of the order Asaphida on the basis of its close morphological similarity to Asaphidae. Postembryonic development of the tsinaniid trilobite, Tsinania canens , from the Furongian (late Cambrian) Hwajeol Formation of Korea, reveals that this trilobite had an adult-like protaspis. Notable morphological changes with growth comprise the effacement of dorsal furrows, sudden degeneration of pygidial spines, regression of genal spines, and loss of a triangular rostral plate to form a ventral median suture. Programmed cell death may be responsible for degenerating the pygidial and genal spines during ontogeny. Morphological changes with growth, such as the loss of pygidial spines, modification of pleural tips, and effacement of dorsal furrows, suggest that T. canens changed its life mode during ontogeny from benthic crawling to infaunal. The protaspid morphology and the immature morphology of T. canens retaining genal and pygidial spines suggest that tsinaniids bear a close affinity to leiostegioids of the order Corynexochida. Accordingly, development of a ventral median suture in T. canens demonstrates that the ventral median suture could have evolved polyphyletically, and thus the current concept of the order Asaphida needs to be revised.     

沙区生态系统恢复演变过程中固沙植物种间生态位关系变化的研究

以演变时间为生态位维 ,通过分析物种的生态位体积和生态位重叠 ,研究了荒漠生态系统恢复演变过程中固沙植物种间生态位关系的变化 ,同时也探讨了物种更替的生态学机制。这一研究对于实现沙区固沙植物群落的持续发展具有重要的指导意义     

黄河首曲-玛曲县高寒草甸沙化演替进程中群落结构及种群生态位特征

以甘肃省玛曲县高寒沙化草甸为对象,应用空间序列代替时间序列的方法,对其不同沙化演替阶段植物群落主要种群结构及其生态位特征进行了研究.结果表明:(1)随着沙化演替的进行,物种组成数呈单峰式曲线变化规律,在轻度沙化阶段物种数最多(43种),禾草类和豆科类物种的重要值和生态位宽度均呈逐渐减少规律,优势度逐渐减弱;在极度沙化阶段(除垂穗披碱草外)几乎完全消失,莎草类和杂类草一些物种的重要值和生态位宽度则均呈逐渐增大规律,优势度逐渐增加,并在重度或极度沙化阶段成为优势种、次优势种或重要伴生种;随沙化演替进程,蒲公英、狼毒和乳白香青等物种则表现出波动性,最后消失,物种组成和数量的变化导致沙化演替进程中高寒草甸草场质量逐渐降低.(2)相邻沙化演替阶段植物群落的物种组成相似性指数较高,而相距较远的沙化演替阶段植物群落的物种组成相似性指数较小,沙化演替系列两个极端阶段的植物群落的物种组成相似性指数最小.(3)垂穗披碱草在整个沙化演替过程中重要值和生态位宽度均逐渐减小,但其值都较大.(4)生态位总宽度占前5位的物种依次是:垂穗披碱草、莓叶委陵菜、矮嵩草、高山唐松草和苔草,其值分别为1.653、1.438、1.387、1.295和1.204.(5)种群之间生态位重叠系数的平均值随沙化程度加深呈单峰式曲线变化规律,轻度沙化阶段种群的生态位重叠程度较高,为0.824.     

古浪县北部荒漠植被主要植物种的生态位特征

利用Shannon-Wiener生态位宽度公式和Pianka生态位重叠公式,计测分析了甘肃省古浪县北部荒漠植被主要植物种在不同植被演替阶段的生态位宽度和生态位重叠。结果表明:在流动沙地上花棒的生态位宽度最大,其次是沙蒿;在半固定沙地上白刺的生态位宽度最大;在固定沙地上,不论是封育植被还是未封育植被中均是花棒的生态位最宽。同一植物种的生态位随着植被演替阶段的变化而发生变化,这种变化反映了不同演替阶段下的植被恢复效果。优势种的生态位重叠大,生态位宽的物种对重叠值也大,相同物种对在不同演替阶段的生态位重叠不一致。有些物种生态位宽度窄,但重叠值大,是由荒漠植被区物种分布存在生境斑块现象造成的。     

中国云南细颚猛蚁属五新种一新记录种记述 (膜翅目 :蚁科)(英文)

记述采自云南西双版纳细颚猛蚁属LeptogenysRoger 5新种 :黄帝细颚猛蚁L .huangdiisp .nov .,盘古细颚猛蚁L .panguisp .nov .,庄子细颚猛蚁L .zhuangziisp .nov .,老子细颚猛蚁L .laoziisp .nov .,孟子细颚猛蚁L .mengziisp .nov .。在同一地区发现中国新记录种 1种 :粗角细颚猛蚁L .crassi cornisEmery。编制了细颚猛蚁属中国已知 13种的工蚁分种检索表。提供了除勃固细颚猛蚁L .peuqueti(Andre)外 12个种的详细特征图。中国已知种类被划分为 4个种组 :粗角细颚猛蚁种组L .crassicornis group ,中华细颚猛蚁种组L .chinensis group ,条纹细颚猛蚁种组L .diminuta group和庄子细颚猛蚁种组L .zhuangzii group。     

The role of local knowledge in determining shade composition of multistrata coffee systems in Chiapas,Mexico

This research explores interactions between farmers’ knowledge and socioeconomic circumstances and the floristic composition of multistrata coffee plantations in Chiapas, Mexico. Interviews with 24 individual farmers with accompanying vegetation transects and two community level participatory workshops were carried out. The frequency, density, dominance, utility and importance value for all tree species surveyed were obtained. Farmers were grouped by cluster analysis on the basis of their land area, time producing coffee and the age of their coffee farms but the dominant shade species in their coffee plantations was not influenced by socioeconomic status (p<0.05). A total of 74 shade species were recorded and classified as temporary, suitable, or unsuitable as shade species by farmers, based on attributes such as leaf phenology, foliage density, crown shape and the amount and timing of litter decomposition, as well as their overall impact on coffee yield. Principal component and cluster analysis using these attributes confirmed the consistency of the farmers’ classification system. A group of preferred species was identified, but less than half the trees recorded on farms were of these species, showing that farmers retained a wide range of trees and shrubs in their plantations, taking into account not only commercial interests but also their contribution to ecosystem functions. Farmers harnessed the forces of secondary succession by retaining pioneers as temporary shade, knowing that they would naturally be succeeded, while at the same time promoting and tolerating other longer living native species that they considered more suitable as coffee shade. Managing diverse secondary succession instead of establishing monospecific shade was an efficient way for farmers to achieve acceptable coffee yields while contributing to biodiversity and landscape conservation that could allow them access to niche markets.     

Eyes and vision in the coeval Furongian trilobites Sphaerophthalmus alatus (Boeck, 1938) and Ctenopyge (Mesoctenopyge) tumida Westergård, 1922, from Bornholm,Denmark

The two olenid species Sphaerophthalmus alatus (Boeck, 1838) and Ctenopyge (Mesoctenopyge) tumida Westergård, 1922, occur together in the Ctenopyge tumida Zone (Zone 19) of the Furongian of Scandinavia. Material from Bornholm, Denmark, forms the basis of this study of the morphology and partial ontogeny of the eyes. The eyes of both species are directed laterally and have virtually panoramic vision, looking out sideways like those of a rabbit. The eye of S. alatus is comparatively smaller, with fewer lenses and a larger eye parameter; calculations show that this trilobite was adapted for dim light intensity, possibly suggesting a vagrant benthic habit. Ctenopyge (Mesoctenopyge) tumida, with a smaller eye parameter, was adapted for a higher light intensity, and this trilobite was most likely a pelagic swimmer. The two species, although preserved together, inhabited different levels in the water column.     

Palaeontologic and biogeochemical characterization of the Cyrtograptus lundgreni event in the black shales of eastern Mid-Sardinia, Italy

A succession of biotic and geochemical changes that occurred during the Cyrtograptus lundgreni Event (Late Wenlock) have been recorded from the 'pelagic' black-shales in the Goni section, eastern mid-Sardinia, Italy. The studied interval encompasses the Cyrtograptus rigidus to Pristiograptus dubius-Gothograptus nassa zones. The fossil association includes graptolites, chitinozoans and microplankton i.e. probable linings of agglutinated foraminifera and radiolaria capsular membranes. Analysis of the chitinozoan distribution revealed a succession of several chitinozoan associations with low species diversity and dominated by opportunistic species. Three chitinozoan faunal turnovers and three extinction events have been recorded. Two of them coincide with graptolite extinctions whereas one probably is of local significance. Disappearance of the chitinozoan and microplankton associations occurred during four consecutive graptolite zones. Geochemical data (trace elements analysis) showed significantly higher (up to c. 100%) values for Co and Cd in the sedimentary organic matter (SOM) than in the whole rock samples. Possible relationships between peaks of metal enrichment, the major faunal changes among chitinozoans, extinction events among chitinozoans and graptolites and, to a certain extent, oceanic events may be inferred. The first extinction datum is older that those occurring in Gotland, Sweden and Thüringen, Germany and is so far considered to be of local significance. The second extinction datum of Sardinia can be matched with Datum 1 of Gotland and Thüringen. A close correlation between the third extinction datum of Sardinia and Datum 2 of Thüringen and Gotland reinforces the importance of these events at global scale.     

Die Graptolithen des Ordoviziums von Rügen (Norddeutschland, Vorpommern)

Graptolite faunas from theHolmograptus lentus,Pterograptus elegans, Hustedograptus teretiusculus andNemagraptus gracilis Zones are identified in the Ordovician succession of Rügen. The well sections bear incomplete, often fault-bounded successions. Tectonic stacking is present in the Rügen 3h core. A sedimentological gap is expected in the Arenig. About twenty graptolite species are described and their local biostratigraphic ranges are documented. Most of the faunal elements are described for the first time from the Ordovician of northern Germany. The faunal associations belong to the Atlantic Faunal Province.     

豫西北太原组的时代:来自类化石的证据

在河南省焦作地区太原组典型剖面上,共鉴定出类11属18种及11个未定种。根据类的组合特征,建立了一个类化石带两个亚带:Sphaeroschwagerina延限带,Quasifusulina-Pseudofusulina组合亚带和Schwagerina-Boultonia组合亚带。类在该区的出现次序是:Sphaeroschwagerina→Pseudofusulina→Quasifusulina→Schwagerina,其组合特征与当时华北板块大规模海侵密切相关。根据焦作太原组L1灰岩中首现Sphaeroschwagerina及类的演替特征等证据,石炭系-二叠系(C-P)界线应在太原组L1灰岩之下,太原组应划归下二叠统。     

科尔沁沙地植物群落恢复演替系列种群生态位动态特征

以科尔沁沙地草地植被恢复过程不同阶段和不同演替时间的6个群落类型的取样为对象。研究了植被恢复过程群落演替序列主要种群的生态位动态特征。结果表明：演替过程每一群落类型优势种的作用明显,具有最大的生态位宽度。生态位宽度在演替序列的动态变化较好地对应着种群动态,生态位宽度是种群动态的一个间接测度。是种群在群落中的地位和作用的数量表达。能够较好地解释群落演替过程种群的环境适应性和资源利用能力。沙米、雾冰藜、狗尾草、差巴嘎蒿、猪毛菜、隐子草分别是演替时间为1a、3a、5a、12a、20a和30a群落的优势种群。在群落演替序列较高的生态位重叠是适宜生境斑块化和空间异质性的结果,同时也反映了演替序列群落的过渡性质以及群落结构的不稳定性。