Marine paleoecology in the Upper Devonian of New York

In the clastic Genesee Group of the Catskill delta, lateral changes of the fauna are believed to reflect onshore-offshore physicochemical gradients. A shoreward increase of infauna is interpreted as adaptation to increased environmental stress. Free immobile taxa were concentrated offshore, while vagile forms, presumably able to cope with shifting substrata, are dominant nearshore. A shorewards replacement of brachiopods by bivalves reflects the eurytopy and infaunal habits of the bivalves.
In Gencsee time, progradation was first rapid, then slow. The sequence is reversed in the superjacent Sonyea Group and the accompanying reversal of faunal patterns is strong evidence of faunal control by the rate of progradation. This indicates the hazardous nature of attempts to trace 'community evolutioneditor' using only a few studies from each period.     

Marine benthic communities in the Upper Devonian of New York

Four distinctive benthic communities occur in the mid-shelf deltaic deposits of the Upper Devonian Sonyea Group: the Bellerophon Community, dominated by herbivorous gastropods and deposit-feeding bivalves; the Prodrtctella Community, dominated by brachiopods with adaptations for life on muddy substrata; the Cypricardella Community, dominated by bivalves and brachiopods with a variety of adaptations; and the Rhipidomella Community, dominated by brachiopods adapted for life on sandy substrata. The geographic and stratigraphic occurrence of the communities suggest that their distribution was controlled by two principal sets of environmental variables: (1) onshore to offshore gradients in salinity, dissolved oxygen concentrations, and sedimentary substrata, and (2) rate of delta progradation. A change in the rate of delta build-out during mid-Sonyea time led to a dramatic change in onshore to offshore community patterns. The change suggests that great care must be used in constructing generalized community models for longer intervals of Paleozoic time.     

Level-bottom brachiopod communities in the Middle Devonian of New York

Depositional environments of the Onondaga Limestone from central to southeastern New York are found to be normal, subtidal marine, due to the absence of characteristic supratidal or intertidal sedimentary features and the presence of a typical, diverse, marine level-bottom community framework. Post-mortem transport has not been extensive, as evidenced by low articulation ratios, lack of abraded valves, and complete ontogenetic gradations within species, which precludes large scale winnowing. Sedimentation rates appear to have been greatest in eastern New York where the Onondaga Limestone reaches a thickness almost three times that of the strata in central New York. Shaly beds in the central area represent periods of cessation of carbonate deposition rather than an influx of clastic material. Deposition terminated with the onset of deeper water characterized by a westerly advance of terrigenous sedimentation (the Marceilus Shale of the Hamilton Group). Nine brachiopod communities can be recognized in the Onondaga Limestone. There is a strong correlation between sediment-substrate and community type, reflecting the sedimentologic control of brachiopod community distribution. Sandy facies, cherty limestones and coral biostromes and bioherms are associated with inner-neritic deposition in Edgecliff time; argillaceous lime muds and lime sands are characteristic of mid-neritic deposition in Nedrow to Moorehouse time; and highly argillaceous lime muds are associated with outer-nerittc deposition in Seneca time.     

New Late Devonian strophomenids (Brachiopoda) from Mongolia

Two new strophomenid species, Leptagonia barunkhuraica sp. nov. (Famennian) and Floweria mongolica sp. nov. (Frasnian), from the Upper Devonian of the Barunkhurai Depression of southern Mongolia are described.     

Ecology and evolution of Devonian trees in New York,USA

The first trees in New York were Middle Devonian (earliest Givetian) cladoxyls (?Duisbergia and Wattieza), with shallow-rooted manoxylic trunks. Cladoxyl trees in New York thus postdate their latest Emsian evolution in Spitzbergen. Progymnosperm trees (?Svalbardia and Callixylon–Archaeopteris) appeared in New York later (mid-Givetian) than progymnosperm trees from Spitzbergen (early Givetian). Associated paleosols are evidence that Wattieza formed intertidal to estuarine mangal and Callixylon formed dry riparian woodland. Also from paleosols comes evidence that Wattieza and Callixylon required about 350 mm more mean annual precipitation than plants of equivalent stature today, that Wattieza tolerated mean annual temperature 7 °C less than current limits of mangal (20 °C), and Callixylon could tolerate temperatures 14 °C less than modern mangal. Devonian mangal and riparian woodland spread into New York from wetter regions elsewhere during transient paleoclimatic spikes of very high CO₂ (3923 ± 238 ppmv), and subhumid (mean annual precipitation 730 ± 147 mm) conditions, which were more likely extrinsic atmospheric perturbations rather than consequences of tree evolution. For most of the Middle Devonian CO₂ was lower (2263 ± 238 ppmv), and paleoclimate in New York was semiarid (mean annual precipitation 484 ± 147 mm). Such transient perturbations and immigration events may explain the 40 million year gap between the late Emsian (400 Ma) evolution of trees and Famennian (360 Ma) CO₂ drawdown and expansion of ice caps.     

A new genus of lycopods from the Devonian of New York State

Drepanophycus colophyllus Grierson & Banks is transferred to llaskinsia Grierson & Banks on the basis of the morphology of its leaves and its anatomical structure. Slender, dichotomizing axes bear helically arranged leaves that are falcate, petiolate, simple, lanceolate and entire. A solid cylinder of metaxylem is surrounded by ridges of protoxylem. Pitting on tracheid walls is annular, helical, reticulate, scalariform to circular-bordered. This lycopod extends from early Givetian into early Frasnian time in the Catskill strata of eastern New York State. The effect of cleavage of fossiliferous rock on patterns observed on the exposed fossils and the bearing of recent research on the fossil history of lycopods are discussed.     

New radiolarians from the Devonian of the southern Ural Mountains: 1. Early-Middle Devonian (Late Emsian-Early Eifelian)

Late Emsian-Early Eifelian radiolarians from the southern Ural Mountains are recorded and described for the first time. They come from the Kamennaya Gora section on the Tanalyk River near the town of Buribay, Bashkiria. The new Late Emsian-Early Eifelian radiolarian assemblage consists of 20 species of 11 genera of spherical, discoidal, spindle-shaped, pylomate, and spiny radiolarians. Four new species, i.e., Entactinia rostriformis sp. nov., Palaeodiscaleksus tumefactus sp. nov., Primaritripus buribayensis sp. nov., and P. chuvashovi sp. nov., are described. The diagnosis of the genus Primaritripus Afanasieva, 2000 is amended. The fact that the oryctocenosis is dominated by discoidal radiolarians suggests that, in the Late Emsian-Early Eifelian, the area under study was occupied by a relatively shallow marine basin. Based on radiolarians, a new Upper Emsian-Lower Eifelian biostraton, beds with Primaritripus buribayensis-Entactinia rostriformis, is established. The history of the study of Early Devonian radiolarians is considered.     

Turbulence-controlled succession in Middle Devonian reefs of eastern New York State

Wolosz. T. H. 1992 07 15: Turbulence-controlled succession in Middle Devonian reefs of eastern New York State.
The Edgecliff Member ol the Middle Devonian Onondaga Formation contains numerous reefs comprised of two distinct facies. The Phaceloid Colonial Rugosan Facies consists of thickets and mounds, while the Favositid/Crinoidal Sand facies occurs as flank beds surrounding rugosan mounds and as low shield-shaped banks interbedded with thickets of the colonial rugosan facics. Three of these reefs - the North Coxsackie. Albrights and Roberts Hill reefs - have been studied in order to determine the factors that controlled their development and their preserved paleocommunity succession. Both the Roberts Hill and Albrights reefs display well-developed rugosan mounds with an internal succession of rugosan genera. The North Coxsackie reef is a crinoidal sand bank with rugosan thickets and a back-reef satellite mound. Based on the lithology of the underlying limestone in which the reefs are rooted, the North Coxsackie reef is considered to have grown in a shallow-water environment, landwards of the two other reefs. Successional sequences or partial sequences are common to the three reefs, and are found to be reversible - a response attributed to changes in sea-level. As a result, the successions preserved in these reefs are interpreted as having been controlled by degree ol water turbulence.     

New Devonian and Carboniferous bryozoans of the Holy Cross Mountains (central Poland)

New bryozoans from the Middle-Upper Devonian (Eifelian-Frasnian) and the Lower Carboniferous (Tournaisian) of the Holy Cross Mountains in central Poland are described: Bigeyella sparsa gen. et sp. nov., B. separata gen. et sp. nov., Eridopora singula sp. nov., Leptotrypa pulchra sp. nov., Kysylschinipora klarae sp. nov., Coelotubulipora rara sp. nov., Alternifenestella genuina sp. nov., Exfenestella polonica sp. nov., and Rectifenestella localis sp. nov. Some paleogeographic and stratigraphic aspects of the Paleozoic deposits of this region are discussed and main bryozoan localities are described.     

Molecular systematics, zoogeography, and evolutionary ecology of the atlantic parrotfish genus Sparisoma

Parrotfishes of the genus Sparisoma (Scaridae) are ecologically important tropical reef fishes restricted to the Atlantic Ocean. We investigated phylogenetic relationships among the eight extant species within this genus using mitochondrially encoded 12S and 16S ribosomal genes. Our molecular data support the view that (i) Sparisoma originated approximately 14-35 million years ago (mya), probably in the tropical western Atlantic, off Brazil; (ii) there have been at least four discrete bouts of cladogenesis within the genus, with the most recent one ( approximately 2.8-5.6 mya) involving four events in both the east and the west Atlantic and across the Atlantic; and (iii) the genus invaded the eastern Atlantic on two different occasions, probably by at least two different routes. The data also offer support for Bellwood's ideas concerning the evolutionary changes in adult feeding patterns and habitat use within Scarids. Specifically, they support the evolutionary position of the ecological traits of Sparisoma as intermediate within the family.     

New perspective on the architecture of the Late Devonian arborescent lycopsid Leptophloeum rhombicum (Leptophloeaceae)

A reinvestigation of the previously described Leptophloeum rhombicum trunk from the Late Devonian (Frasnian) Huangchiateng Formation of Hubei, China provides a new perspective on the architecture of this arborescent lycopsid. It is preserved as a flattened, silicified petrification with an unevenly permineralized primary vasculature and spirally arranged rhombic leaf cushions, which agree with the diagnosis of L. rhombicum Dawson distributed worldwide in the Late Devonian. Taxonomically, this plant should be assigned to its own family and within the order Iso?tales sensu lato. The anatomy, from different levels of the trunk, demonstrates that the ontogeny of the plant may conform to a determinate growth pattern. Combining previous data with current architectural analysis, it suggested that the L. rhombicum tree had a pseudomonopodial branching pattern rather than an iso-dichotomous branching crown as previously proposed. New reconstruction of the general habit for this tree is given and consists of three major architectural units: a stigmarian rhizomorph, a main trunk, and lateral branches. When these results are considered with recent cladistic work, L. rhombicum may have developed similar growth architecture to some Famennian and Carboniferous arborescent lycopsids. This growth represents one of the archetypal architectures found in the Iso?tales s.l. extending from the early Late Devonian.     

Upper Devonian Cyrtospirifer and related genera of the Canadian West and a provisional comparison with those from the Appalachians

Study reveals that 8 species of Cyrstospirifer: C. chemungensis, C. kennicotti, C. thalattodoxa, C. whitneyi, C. charitopes, C. hornellensis, C. alexandrae, C. inermis, 6 of Crytiopsis: C. mimetes, C. prepta, C. nahanniensis, C. normandvillana, “C”. hiraethlynae and C. kindlei, 4 of Tenticospirifer: T. sp. A, T. sp. B, T. kelecticus and T. standlyensis, 2 species of Eochoristies: E. protistus and E. glennfoxi and one species presumed to be a Spirifer: S. zantedeschii are present in the Canadian West, all with well-defined zones in the Frasnian and Famennian.Prelimanary comparison with similar groups in the classic Upper Devonian of the Appalachians shows that nine of these, or 45%, are identical species present in both provinces.     

A survey of hymenopteran parasitoids of forest macrolepidoptera in the central Appalachians

In 1995 and 1996, we conducted a study of the hymenopteran parasitoids of macrolepidopteran larvae in the George Washington National Forest (GWNF), Augusta County, Virginia, and the Monongahela National Forest (MNF), Pocahontas County, West Virginia. Macrolepidopteran larvae were collected from canopy foliage and from under canvas bands placed around tree boles. A total of 115 macrolepidopteran species and 5,235 individual larvae were reared. Forty-two percent (2,221) of the larvae were gypsy moth, Lymantria dispar (L.) (Lymantriidae). A total of 43 primary and secondary (hyperparasitoid) hymenopteran parasitoid species were reared from 46 macrolepidopteran species. Hymenopteran families represented included Ichneumonidae (23 species), Braconidae (19), Eulophidae (6), Perilampidae (1), and Trigonalidae (1). We reared 41 and 28 parasitoid species from the GWNF and the MNF, respectively, with 19 species reared from both forests. Many parasitoid species were collected infrequently, suggesting that they are relatively rare on the sampled hosts. The introduced species Cotesia melanoscela (Ratzeburg) (Braconidae), and Euplectrus bicolor (Swederus) (Eulophidae) were among the most commonly reared parasitoids, the latter reared from native hosts. The four most commonly reared native parasitoids were Meteorus hyphantriae, Riley (Braconidae), Microplitis near hyphantriae (Ashmead) (Braconidae), Aleiodes preclarus Marsh & Shaw, and Euplectrus maculiventris (Westwood) (Eulophidae). A total of 53 new hymenopteran parasitoid-macrolepidopteran host records were documented. Results from this study will be used to evaluate long-term treatment effects of regional applications of Bacillus thuringiensis kurstaki, and the gypsy moth fungus Entomophaga maimaiga Humber, Shimazu & Soper on hymenopteran parasitoids of macrolepidopteran larvae.     

A New Late Silurian or Early Devonian Thelodont from the Boothia Peninsula, Arctic Canada

Isolated scales of Boothialepis thorsteinssoni gen. et sp. nov. are described from a fossiliferous calcareous dolomite at the base of the Somerset Island Formation of the Boothia Peninsula, Arctic Canada. A new family, Boothialepididae (Thelodonti), is established on features of the scale morphology and histology. The new genus and species are distinguished by characteristics of crown sculpture, neck, and unusual size of the base. Two other thelodonts, Nikolivia elongata Karatajūtė-Talimaa and Canonia grossi Vieth, and an acanthodian, Poracanthodes sp., are described from the same stratigraphical level. Thelodonts have not previously been described from the Boothia Peninsula. Conodont-based correlation indicates a Late Silurian age for the base of the Somerset Island Formation on the Boothia Peninsula. Correlation of the beds with precisely dated microvertebrates in the Read Bay section on Cornwallis Island enables the age of the horizon with the new species to be determined as Early Devonian.     

The anatomy of Pseudosporochnus: P. Hueberi from the Devonian of New York

Eight structurally preserved specimens originally called Cladoxylon onteorense nom. nud. Hueber 1959, from Hensonville, New York, Cladoxylon dichotomum nom. nud. Hueber 1960 from East Ashland, N.Y., and Cladoxylon hueberi Matten 1974 from East Ashland and Cairo, N.Y., are analyzed in detail for their morphological and systematic significance. The type of C. hueberi from East Ashland, by far the most important specimen, provides the first opportunity in any Devonian member of the Cladoxylopsida for a realistic three-dimensional assessment of the primary xylem system. A main axis contains a highly dissected primary xylem system with 40–50 longitudinally anastomosing primary xylem segments. Distally, the main axis dichotomizes producing two equal branches with 20–25 xylem segments each. The outermost primary xylem consists of a system of radially oriented tracheid plates variously interconnected toward the inside, each with a conspicuous protoxylem strand near the xylem periphery. Traces to densely and three-dimensionally, but not helically, arranged lateral appendages depart singly or in groups of two or three from one to three adjacent peripheral-radial xylem plates. Although direct evidence on the external morphology of lateral appendages is not preserved, many trace groups exhibit conspicuous bilateral symmetry consistent with the interpretation of planate lateral appendages similar to those described for Pseudosporochnus nodosus. Other trace groups may indicate more three-dimensional lateral appendages. One sub-opposite pair of clepsydroid traces is borne at right angles to, and in obvious relationship with, the dichotomy of the main axis. Cortex is heterogeneous, consisting of thin-walled parenchyma with embedded clusters of sclereids and thick-walled parenchyma. These clusters appear responsible for a regular pattern of bumps or pits in compressed regions of the specimen and are closely comparable to those observed in Pseudosporochnus nodosus. A systematic analysis, attempting to view fragmentary evidence from both compressions and permineralizations in a single coherent framework, leads us to hypothesize assignment of the East Ashland and Hensoville specimens to the genus Pseudosporochnus. Although supported by the evidence, the hypothesis of assignment is by no means proven. We propose it, however, because we think that advancing systematic hypotheses conspicuously at risk of being refuted by additional observation promotes far greater understanding than taking an agnostic stance toward systematics implied by the use of “form” taxa. We further clarify our position by suggesting specific observations likely to be made from fossil specimens that might refute our hypothesis.     

Marine faunal assemblages in the Silurian-Devonian Keyser Limestone of the central Appalachians

Sedimentological analysis of the Keyser Limestone (Upper Silurian - Lower Devonian of the central Appalachians) indicates that its sediments were deposited in a range of marginal and shallow marine environments. Major depositional environments include: tidal flat, lagoon, barrier bar and island, and open marine shelf. Each major environment is represented by a lithofacies which is lithologically and faunally distinct. Tidal flat lithofacies are characterized by eurytopic organisms, including ostracodes, gastropods, stromatoporoids and blue-green algae. Lagoon lithofacies are dominated by bryozoans, brachiopods, ostracodes and stromatoporoids. Barrier lithofacies are characterized by rooted crinoids, encrusting bryozoans and robust brachiopods. Open shelf lithofacies contain a diverse fauna of cystoids, crinoids, bryozoans and brachiopods.
The distributions of faunal assemblages in the Keyser show no simple relationship to either water depth or distance from shore. They are, in general, related to the distributions of depositional environments.
Recurring associations of brachiopod genera were not found in the Keyser. With few exceptions, any genus may be found in any subtidal environment. Abundance of brachiopods is related to the abundance of local hard substrates (usually bryozoans).     

The culture of marine ecology

Marine algal ecology today faces many of the same problems as ecology in general, e.g. lack of generality of experimental results, the difficulty of making long-term predictions, and an apparent lack of agreement as to what constitutes the proper or `acceptable' way of doing this particular component of science. These problems, if real, affect marine algal ecology everywhere but, in different geographical areas, specific problems also occur; science in parts of Asia has some problems different from those in other parts of the world. Since its inception, research in marine algal ecology has been motivated by many factors, ranging from traditional needs, to curiosity, to survival, to new technology, and economic needs. Each of these has shaped the questions that have been asked by, and the level of support society has been willing to supply to, ecology. For example the requisites of tradition pushed marine ecology to ask questions about food and ceremonial biota, and our fears today about loss of biota are pushing for answers to questions about the means of preserving biodiversity. The limitations of many marine ecological studies have been pointed out by different individuals. Their comments have been valuable in forcing us to examine what we are doing as marine ecologists, and how we are doing it. Ecology, and marine algal ecology with it, has been accused of carrying out small-scale studies that have no greater generality than the sites at which the studies were done, and of using statistical procedures that are wrong or inappropriate; also, there is disagreement within the ecological community of how to correct for these `faults'. Some of the problems arise due to the nature of our particular science, e.g. working with organisms with differing genetic makeup and sensitivity of experimental results to small changes in initial conditions. Other problems are more likely due to the individuals doing the science, e.g. an inability to be an `expert' on all areas of knowledge required for a modern ecologist (taxonomy, experimental design, data analysis, etc.), and perhaps an unwillingness to recognize that in some instances different methods of data analysis are applicable and valid. As ecologists, we must come to grip with these problems, both for the sake of our science, and for our own sake as practicing ecologists.     

Sclerite-bearing alveolitid favositids from the Devonian of central Poland

Calcitic and pyritic pseudomorphs of originally siliceous monaxonic sclerites (predominantly heloclone-like monocrepid desmas) have been found entrapped within calcareous skeletons of alveolitid favositids identified as Squameoalveolites fornicatus (SchlÜter 1889) derived from Lower and Middle Devonian (Emsian and Eifelian) deposits of central Poland. The sclerites are arranged in a system of subvertical tracts forming a loose palisade along the midwall of skeletal tubes. Poorly preserved remnants of such palisades correspond to the so-called »median line« or »median suture« of typical favositids. The finding supports the hypothesis of poriferan affinity of favositid Tabulata and indicates that these common Palaeozoic fossils cannot be longer classified as Cnidaria. They should, on the basis of the sclerites, be regarded as remnants of monaxial and/or sublithistid demosponges, which - like the members of modern and fossil demosponges called sclerosponges or coralline sponges - had the ability to produce a basally secreted calcareous skeleton in addition to siliceous sclerites.     

Supply-side ecology and benthic marine assemblages

Many marine invertebrates have a planktonic stage of their life history during which widespread dispersal and much mortality occur. The numbers surviving to recruit into habitats occupied by adults are therefore very variable in time and space. Models for the structure and dynamics of benthic assemblages tend to focus on processes causing death - often assuming consistent arrivals of recruits. Supply-side ecology is a newly fashionable term to describe recent interest in the long-realized consequences of variations in recruitment. Such variations have important influences on theory and empirical research in these assemblages.