A POST‐SCRIPT TO THE ENIGMATIC PROTONYMPHA (DEVONIAN; NEW YORK): IS IT AN ARM OF THE ECHINODERMS?

Abstract:  A unique specimen of the supposed arm of the Middle Devonian (Givetian) starfish Foliaster transversus Blake, 1994[ Journal of Palaeontology , 68, 123–134] is shown to be closely comparable to the enigmatic organism Protonympha salicifolia , also of Devonian age, albeit slightly younger (Frasnian), and also from New York State. Similarities to starfish, or any other echinoderm, appear to be superficial. Differences from the type species of Protonympha are minor, but include the detailed structure of the transverse segments. For this reason a specific distinction is retained, and the taxon Protonympha transversa (Blake, 1994) now proposed. Enigmatic fossils such as Protonympha raised related questions of evolutionary affinity and the problems of pattern recognition. These questions may also touch on the interpretation of organic structures, such as might be returned from Mars (or further afield).     

Reassessment of the Devonian problematicum Protonympha as another post‐Ediacaran vendobiont

Protonympha is an enigmatic fossil represented by two species from the Middle Devonian (Protonympha transversa) and Late Devonian (Protonympha salicifolia) of New York. Although interpreted in the past as a polychaete worm or starfish arm, Protonympha is not found with marine fossils, but with fossil plants. This fossil plant community was a swamp woodland of Lepidosigillaria whitei, with ground cover of Haskinsia colophylla, fringing brackish to freshwater coastal lagoons of the Catskill Delta. Protonympha shares with Ediacaran Vendobionta a quilted body of unskeletonized biopolymer that is unusually resistant to burial compaction. In overall form, Protonympha is most like the Ediacaran genus Spriggina. Protonympha has branching and tapering tubular structures radiating from the bottom. These rhizine‐like structures, thallus stratification and internal chambers revealed by petrographic thin sections suggest affinities with lichenized fungi. As for Cambrian Swartpuntia and Ordovician–Silurian Rutgersella, Protonympha may have been a post‐Ediacaran vendobiont.     

New Silurian cooksonias from dolostones of north-eastern North America

New specimens of Cooksonia and Hostinella are described from the Bertie Group of Ontario and New York State, which is dated by faunas as latest Silurian (Přídolí). The rare plant fossils are unusual in that they are preserved in fine-grained, slightly argillaceous dolostones ('waterlime') rather than clastic rocks. At least two species of Cooksonia are present, one with ± globular sporangial morphology close to C. hemisphaerica Lang. Those with ellipsoidal/discoidal sporangia are compared with C. pertoni Lang, C .  paranensis Gerrienne et al . and C. bohemica Schweitzer, the latter represented by a single specimen from the Přídolí of the Czech Republic. However, the paucity of specimens, which prevents assessment of taphonomic influences on shape, combined with the absence of any anatomical features and the gross morphological simplicity of the fossils, precludes specific assignment. Specimens of Hostinella include one in which apices and a lateral basal structure resembling a root are preserved. It is concluded that the Laurentian assemblage of Ontario and New York State is less diverse and disparate than coeval assemblages, which are also preserved in marine rocks. Its preservation in limestones may have been facilitated by the hypersalinity inferred from various sedimentary features, which would restrict the activity of many decomposers.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 399–413.     

EARLY DEVONIAN BIOEROSION IN THE RADE DE BREST, ARMORICAN MASSIF, FRANCE

Abstract:  Abundant and diverse bioerosion trace fossils in the Lower Devonian of the Rade de Brest, France, were produced by boring ctenostomate bryozoans, polychaete annelids and algae. Two unidentifiable traces of encrusting sclerobionts are also considered. Two new taxa are described: Pinaceocladichnus cristatus ichnosp. nov. and Ichnogutta erectus ichnogen. et ichnosp. nov. Both are attributed to the work of boring bryozoans. Sedimentary condensation during intervals of sea-level rise seems to have had an important influence in promoting infestation by organisms, the activities of which are now preserved as trace fossils. A zonation of bioerosion trace fossils within the offshore zone, in the Lower Devonian of the Armorican Massif, is also suggested.     

SVALBARDIA BANKSII SP. NOV. FROM THE UPPER DEVONIAN (FRASNIAN) OF NEW YORK STATE

Svalbardia banksii sp. nov., is described from the Upper Devonian (Frasnian) Fish Cabin Creek locality near Pond Eddy, New York. The compression consists of ultimate branches bearing spirally arranged, unwebbed leaves. The unwebbed leaves are up to 3.2 cm long, are somewhat flexuous, and dichotomize in more than one plane. The new species is similar to the reconstruction of Actinoxylon banksii from the Middle Devonian (Givetian) of New York and strengthens the supposed relationship between Svalbardia polymorpha and Actinopodium nathorstii from Mimerdalen, Spitzbergen.     

THE CUTICLE OF DREPANOPHYCUS SPINAEFORMIS,A LONG-RANGING DEVONIAN LYCOPOD FROM NEW YORK AND EASTERN CANADA

The presence of paracytic stomata and paired guard cells on specimens presumed to be Drepanophycus spinaeformis Göppert from eastern Canada and New York State supports the conclusion of Banks and Grierson that the species is not a reliable index of Lower Devonian strata. The interpretation of stomatal morphology demonstrates that the species lived in Early, Middle, and Late Devonian time and that slender specimens are distinct from zosterophylls such as Sawdonia that had anomocytic stomata and a single guard cell. Knowledge of the stomata also permits a reinterpretation of the stomatal apparatus as first described by Lang. Siegenian specimens of the genus apparently represent the oldest occurrence of paired guard cells and of paracytic stomata.     

PTERYGOTUS ANGLICUS AGASSIZ (CHELICERATA: EURYPTERIDA) FROM ATHOLVILLE, LOWER DEVONIAN CAMPBELLTON FORMATION, NEW BRUNSWICK, CANADA

Abstract:  Specimens of the large eurypterid Pterygotus from the Early Devonian Campbellton Formation outcropping at Atholville, New Brunswick, are identified as Pterygotus anglicus Agassiz. The locality, in the Atholville beds near the western end of the Campbellton Formation exposure, is best known for its vertebrate fauna of ostracoderms, arthrodires, acanthodians and chondrichthyans, first described in 1881. Although a significant series of pterygotid fossils was acquired by the Natural History Museum, London, in 1892, it received little attention. A few small specimens from the Geological Survey of Canada collections were named Pterygotus atlanticus by Clarke and Ruedemann, considered here to be an invalid taxon. They suggested that P. atlanticus might turn out to be a small specimen of P. anglicus . The new material described here, including one relatively complete individual, confirms their suspicions and provides evidence of Pterygotus anglicus in the Lower Devonian of North America.     

PALAEOBIOLOGY OF THE CLIMACTICHNITES TRACEMAKER

Abstract:  Trace fossils such as Climactichnites offer rare insights into the palaeobiology of Cambrian soft-bodied animals, especially those that inhabited emergent sand flats and are not known from body fossils. Analysis of field and museum Climactichnites , together with experiments on the preservation of similar modern trails, indicates that the tracemaker was an elongate, bilaterally symmetrical, dorsoventrally flattened, soft-bodied animal with a muscular foot. These characteristics are consistent with the tracemaker being a primitive mollusc or mollusc-like animal. Unlike most Neoproterozoic and Cambrian molluscs, the tracemaker could reach considerable size; at up to c . 69 cm long, it was one of the largest Cambrian animals of its time. When moving on the sediment surface, locomotion resulted from muscular waves generated along the sole of its flexible foot; the foot was extended and then clamped onto the substrate. Contraction of pedal muscles then pulled the body forward. Sedimentary structures associated with Climactichnites  wilsoni , such as polygonal desiccation cracks, raindrop impressions, adhesion structures and gas escape structures demonstrate that the animal inhabited intermittently subaerially exposed environments. The tracemaker's method of locomotion is similar to that employed by modern intertidal gastropods, which make Climactichnites -like trails on exposed sand flats. However, these modern trails are not preserved because of erosion by wind, waves, tides and subsequent bioturbation. Abundant microbial sedimentary structures are associated with C. wilsoni , and together with low levels of vertical bioturbation, intimate that microbial binding may have mediated the preservation of these early mollusc trails.     

Devonian monospecific assemblages: new insights into the ecology of reduced-oxygen depositional settings

Low-diversity fossil assemblages interpreted as representing dysaerobic communities are common in the Phanerozoic rock record, and those composed of a single species have particular utility for recognizing the lowest bottom-water oxygen levels. An unusually high-diversity of clades including three rhynchonelliform, two linguliform, and one bivalve species occur in monospecific assemblages within Middle and Upper Devonian black shales of New York State. These six taxa are interpreted to be adapted to extremely reduced bottom-water oxygen levels as inferred from detailed sedimentological data and their repeated monospecific occurrence; however these groups represent two distinct ecologies. Three of these taxa are restricted to sediments deposited under the lowest dysaerobic conditions, while the other three taxa, unlike other fossils characteristic of reduced-oxygen levels, also occur in and are even dominant in high-diversity assemblages. The rhynchonellid brachiopod Eumetabolotoechia multicostata is the most abundant taxon within these units and has a remarkable ecological range as dominant from the lowest dysaerobic zone to near-normal marine oxygen levels. These Devonian groups, when present in monospecific assemblages, have utility for characterizing the lowest dysaerobic zone where trace fossil assemblages, most commonly used to describe these low-oxygen depositional settings, are absent or poorly developed.     

Patesia n. gen., a new Late Devonian stem xiphosurid genus

Xiphosura, the so-called horseshoe crabs, are a group of extant marine chelicerates that have a fossil record extending back to the Lower Ordovician. Their temporal range, coupled with a supposed record of bradytelic evolution has made them a focus of palaeontological consideration for over two centuries. As such, there are an array of taxa erected during the 20^th century that have remained unexamined in light of new material and revised phylogenetic theories. Stem xiphosurids in particular require further research to uncover the diversity and disparity of non-crown group horseshoe crabs. To align with the recent increase in mid to late Paleozoic horseshoe crab research, we reconsider the stem xiphosurids “Kasibelinurus” randalli and “Bellinurus” alleganyensis from the Late Devonian of Pennsylvania and New York State. We conclude that they are synonyms and belong in neither Kasibelinurus nor Bellinurus, and the new genus, Patesia, is erected to accommodate them. Reconsidering stem xiphosurids highlights that particularly in the Late Devonian there was a high disparity of form. One such stem xiphosurid may represent the morphological stock that gave rise to the Carboniferous taxa and the first xiphosurid radiation.     

First Mesozoic Scutigeromorph Centipede, from the Lower Cretaceous of Brazil

The first Mesozoic scutigeromorph centipede (Myriapoda: Chilopoda), Fulmenocursor tenax gen. et sp. nov., is described from the Lower Cretaceous (Aptian) Crato Formation of north-east Brazil. Previously described fossil Scutigeromorpha are known from Dominican and Baltic amber, the Carboniferous (Westphalian D) Francis Creek Shale of Mazon Creek, Illinois, the Silurian and Devonian of Britain, and the Devonian of New York State.     

New insights into early land ecosystems: a glimpse of a lilliputian world

Small, relatively uncompressed, very fragmentary plant remains (mesofossils) are described from a Silurian (P ídolí) and a Lower Devonian (Lochkovian) locality in the Welsh Borderland. Excellent cellular preservation provides characters leading to the demonstration of diversity in plants of simple gross morphology and allows deliberations on functional anatomy (e.g. of stomata), and reproductive biology (including development and dehiscence of sporangia). A survey of in-situ spores is presented, and preliminary comparisons made with dispersed spore assemblages especially in relation to reconstruction of vegetation on local and regional scales. The earliest body fossils of unequivocal terrestrial arthropods isolated from the same locality as the P ídolí plants suggest that the decomposer/microherbivore/predator soil and litter communities found in the Lower and Middle Devonian extend back at least into the Silurian. Evidence for plant—animal interaction in the Lower Devonian comes from spore-dominated coprolites believed to have been produced by litter-feeding myriapods.     

Morphological study on the Devonian zosterophyll Serrulacaulis Hueber and Banks: New materials and emendation

The generic diagnosis of the Mid–Late Devonian zosterophyll Serrulacaulis Hueber and Banks is emended based on morphological study on specimens from New York State (USA), Belgium and Venezuela, and new materials of S. spineus n. sp. from the Middle Devonian Hujiersite Formation of Xinjiang, Northwest China. The new species S. spineus has bilateral obdeltoid emergences and sparsely arranged spines on the axis surface, alternately arranged, reniform sporangia with unequal valves. A variety of the axial emergence appearances of Serrulacaulis is noted, which further indicates easily recognizable features of the genus.     

Furrows and firmgrounds: evidence for predation and implications for Palaeozoic substrate evolution in Rusophycus burrows from the Silurian of New York

Tarhan, L.G., Jensen, S. & Droser, M.L. 2011: Furrows and firmgrounds: evidence for predation and implications for Palaeozoic substrate evolution in Rusophycus burrows from the Silurian of New York. Lethaia, Vol. 45, pp. 329–341. The Silurian Herkimer Formation of east‐central New York contains abundant, exceptionally preserved composite Rusophycus‐Teichichnus burrows. We suggest that the most likely interpretation of these composite trace fossils is as structures formed by trilobites entering the sediment in search of prey. Parallel alignment of the paired traces, asymmetrical configuration of the Teichichnus along the longitudinal axis of the associated Rusophycus, depth correlation and deformation of the Teichichnus all suggest that this relationship was predatory. In addition, sectioned material indicates that these Rusophycus may have been open at the sediment‐water interface, while the crisp preservation of both Rusophycus and Teichichnus, along with the preservation of such delicate morphological details as scratch marks, suggests that the sediment must have been relatively firm at the time the traces were formed. The formation and preservation of Rusophycus in cohesive sediments located very close to the sediment‐water interface hold important implications for the manner in which we consider Palaeozoic substrates and their temporal and spatial evolution. Moreover, these findings demonstrate that the morphology and taphonomy of ichnological associations may, in the context of sedimentological relationships, prove a powerful proxy for tracking substrate conditions through both space and time. □firmgrounds, New York, predation, Rusophycus, substrate, taphonomy.     

AN ASSESSMENT OF VARIABILITY IN THEROPOD DINOSAUR REMAINS FROM THE BATHONIAN (MIDDLE JURASSIC) OF STONESFIELD AND NEW PARK QUARRY, UK AND TAXONOMIC IMPLICATIONS FOR MEGALOSAURUS BUCKLANDII AND ILIOSUCHUS INCOGNITUS

Abstract:  The assemblage of large-bodied theropod remains from the Taynton Limestone Formation (middle Bathonian) of Stonesfield, Oxfordshire and the Chipping Norton Limestone Formation (lowest Bathonian) of New Park Quarry, Gloucestershire, UK is interpreted as monospecific. An assessment of morphological variation in theropod fossils from these localities reveals no taxonomically-significant variation among remains representing large-bodied individuals. Previous observations of anatomical variation among femora, ilia and scapulocoracoids are attributed to postmortem damage and deformation. Referral of all such material to the first named dinosaur taxon, Megalosaurus bucklandii Mantell, is therefore justified. ' Iliosuchus incognitus ' lacks autapomorphies and is a nomen dubium . However, other remains of small-bodied theropods from Stonesfield indicate a minimum of two small-bodied taxa that are distinct from M. bucklandii.     

DEVONIAN TRILOBITES FROM THE FALKLAND ISLANDS

Abstract:  New trilobite material is described from the Fox Bay Formation (Lower Devonian; Pragian) of the Falkland Islands (South Atlantic). The fossils were collected from many localities in both East and West Falkland and represent the first significant collection of trilobites from East Falkland. The trilobites belong to three higher taxa: Proetida (the first proetid record in these islands); Homalonotidae, Burmeisteria Salter, 1865; and Calmoniidae, including Bainella Rennie, 1930 and Metacryphaeus Reed, 1907. All of the forms except proetids have now been found in both East and West Falkland.     

Endolith associations and their relation to facies distribution in the Middle Devonian of New York State, U.S.A.

Vogel, Klaus, Golubic, Stjepko & Brett, Carlton E. 1987 07 15: Endolith associations and their relation to facies distribution in the Middle Devonian of New York State, U.S.A.
Microborings of endolithic organisms (e.g. algae, fungi) provide valuable indicators of paleoenvironments. The present study documents the distribution of microborings in fossil skeletal substrates from a spectrum of shelf to basinal facies in the Middle Devonian of New York. Endolithic boring in brachiopod shells and corals were prepared using special embedding-casting method and were examined and photographed with SEM. About 13 distinct types of microborings were discovered, presumably produced by microorganisms (pro- and eukaryotic), sponges, bryozoans and worms. Brachiopod holdfast etchings are reported for the first time from Paleozoic rocks. Microborings are non-randomly distributed among Middle Devonian facies. The highest diversity and abundance of borings occurs in diverse brachiopod and coral-bearing calcareous mudstones; which appear to represent shallow, well-aerated and low turbidity environments. Microboring diversity and frequency decreases markedly into mudstones and siltstones recording higher turbidity as well as into dark gray to black basinal shale facies. 'Leiorhynchus' brachiopods from probable deeper water, dysaerobic environments display very low diversity of micro-boring assemblages. They include brachiopod pedicle borings and one endolith which shows similarities to a modem cyanobacterium. If the latter is correctly identified, it brackets all of the studied facies within the photic zone.     

中国泥盆纪含鱼化石地层的世界对比

简要回顾泥盆纪含鱼化石地层分层的进展及现状,总结中国泥盆纪含鱼化石地层的层位,横向地比较了主要鱼化石的系统关系,再结合具体的地质历史背景,对比世界有关的地层。     

Evolutionary biology of the Devonian Brachiopoda of New York State: no correlation with rate of change of sea-level?

McGhee, G. R., Jr. 1992 04 15: Evolutionary biology of the Devonian Brachiopoda of New York State: no correlation with rate of change of sea-level?Lethaia, Vol. 25, pp. 165–172. Oslo. ISSN 0024–1164. Previous study has revealed the surprising lack of a relationship between relative sea-level position and the evolutionary biology of the Brachiopoda during the Devonian. To further explore this seeming anomaly, the potential relationship between the rate of change of sea-level and the evolutionary biology of these sessile benthic organisms is analyzed here. Successive linear modeling reveals a lack of correlation between the rate of change of sea-level and either extinction rate, origination rate, or diversity of the Devonian brachiopods. *Sea-level, rate of sea-level change, extinction, origination, diversity, Brachiopoda.