Tenure of individual larval trematode infections in an estuarine gastropod

2003 ◽  
Vol 83 (5) ◽  
pp. 1047-1051 ◽  
Author(s):  
Lawrence A. Curtis
Keyword(s):  
North America ◽  
Salt Marshes ◽  
East Coast ◽  
Single Species ◽  
The Other ◽  
Trematode Species ◽  
Infection Status ◽  
Ilyanassa Obsoleta ◽  
Larval Trematode ◽  
Trematode Infections

Ilyanassa obsoleta (Mollusca: Gastropoda) is an abundant inhabitant of salt marshes and tidal flats on the east coast of North America. Populations of this snail may be heavily infected by larval trematodes. Three species were observed in this work, Himasthla quissetensis, Lepocreadium setiferoides, and Zoogonus rubellus. Mostly as single-species infections, all occupy snail tissues as parthenitae that produce cercariae, which are released from the snail to infect the next host. By periodically testing snails for cercarial emission, single-species infections are here shown to persist over six summers and double-species infections are also noted to be long-lived. Among the 32 snails followed, 25 released the same (or no) cercariae throughout observation periods averaging three years. The other seven indicated infection changes, but only two of these are judged to reflect actual changes. The probability that a snail changed infection status in this study is thus 2.1% y−1. Ilyanassa obsoleta individuals, and apparently their trematode infections, can persist for decades. Because species colonize and get evicted infrequently, sets of trematode species infecting I. obsoleta individuals (infracommunities) are concluded to be isolationist in character.

Fungi on Juncus roemerianus. 8. New bitunicate ascomycetes

1996 ◽  
Vol 74 (11) ◽  
pp. 1830-1840 ◽  
Author(s):  
Jan Kohlmeyer ◽  
Brigitte Volkmann-Kohlmeyer ◽  
Ove E. Eriksson
Keyword(s):  
United States ◽  
Salt Marsh ◽  
Salt Marshes ◽  
New Genus ◽  
East Coast ◽  
The United States ◽  
The Other ◽  
Juncus Roemerianus

Heleiosa barbatula gen. et sp.nov., Massariosphaeria erucacea sp.nov., and Scirrhia annulata sp.nov. are described from Juncus roemerianus in salt marshes of the United States east coast. Whereas H. barbatula is very rare, the other two species do not show a seasonality because they occurred in almost every one of the monthly collections made throughout 2 years. The new genus Heleiosa is of unknown affinity but may belong to Dothideales s.l. Keywords: ascomycetes, Heleiosa, Juncus, Massariosphaeria, salt marsh, Scirrhia.

Effects of interspecific competition on asexual proliferation and clonal genetic diversity in larval trematode infections of snails

Parasitology ◽  
2008 ◽  
Vol 135 (6) ◽  
pp. 741-747 ◽  
Author(s):  
D. B. KEENEY ◽  
S. BOESSENKOOL ◽  
T. M. KING ◽  
T. L. F. LEUNG ◽  
R. POULIN
Keyword(s):  
Genetic Diversity ◽  
Parasite Species ◽  
Clonal Diversity ◽  
Parasite Infection ◽  
Trematode Species ◽  
Larval Trematode ◽  
Parasite Abundance ◽  
Abundance And Diversity ◽  
Trematode Infections ◽  
Antagonistic Interactions

SUMMARYInteractions among different parasite species within hosts can be important factors shaping the evolution of parasite and host populations. Within snail hosts, antagonistic interactions among trematode species, such as competition and predation, can influence parasite abundance and diversity. In the present study we examined the strength of antagonistic interactions between 2 marine trematodes (Maritrema novaezealandensis and Philophthalmus sp.) in naturally infected Zeacumantus subcarinatus snails. We found approximately the same number of snails harbouring both species as would be expected by chance given the prevalence of each. However, snails infected with only M. novaezealandensis and snails with M. novaezealandensis and Philophthalmus sp. co-occurring were smaller than snails harbouring only Philophthalmus sp. In addition, the number of Philophthalmus sp. rediae was not affected by the presence of M. novaezealandensis sporocysts and the within-host clonal diversity of M. novaezealandensis was not influenced by the presence of Philophthalmus sp. Our results suggest that antagonistic interactions may not be a major force influencing the evolution of these trematodes and that characteristics such as host size and parasite infection longevity are shaping their abundance and population dynamics.

Absorption of nutrient exudates from terrapin eggs by roots of Ammophila breviligulata (Gramineae)

1988 ◽  
Vol 66 (4) ◽  
pp. 714-718 ◽  
Author(s):  
Edwin W. Stegmann ◽  
Richard B. Primack ◽  
George S. Ellmore
Keyword(s):  
North America ◽  
East Coast ◽  
Sand Dunes ◽  
Nutrient Supply ◽  
The Other ◽  
Malaclemys Terrapin ◽  
Ammophila Breviligulata ◽  
Dune Soil ◽  
Poor Soil ◽  
Dominant Grass

Ammophila breviligulata Fem. is a dominant grass in the nutrient-poor soil of sand dunes along the east coast of North America. More than half its range overlaps that of Malaclemys terrapin Schoepff., a brackish water turtle nesting in sand dunes. Roots of A. breviligulata often proliferate around buried terrapin nests. Gamma spectrometry was used to determine whether nutrients are translocated from terrapin eggs into A. breviligulata. Eggs, collected in the field within 48 h of being laid, were injected with 75Se, 137Cs, 54Mn, and 59Fe. Labelled eggs were covered with dune soil in pots containing A. breviligulata. Plants were then monitored over 15 weeks for the appearance of isotopes. Within 45 days, all isotopes except 59Fe were found in aerial shoots, more than 30 cm from buried eggs. Iron was absorbed but remained in the roots. The other three isotopes steadily accumulated in shoots for 90 days, after which they began to be translocated to underground tissues. Thus, A. breviligulata absorbs nutrients exuding from buried terrapin eggs, utilizing this novel nutrient supply in mineral-deficient soils of barrier dunes.

Phylogeny of the Crepidula plana (Gastropoda: Calyptraeidae) cryptic species complex in North America

2000 ◽  
Vol 78 (8) ◽  
pp. 1500-1514 ◽  
Author(s):  
Rachel Collin
Keyword(s):  
North Carolina ◽  
North America ◽  
Species Complex ◽  
East Coast ◽  
Sequence Data ◽  
Single Species ◽  
The United States ◽  
Molecular Techniques ◽  
Dna Sequence Data ◽  
Cryptic Species Complex

The taxonomy of Crepidula species with flat white shells is particularly difficult. These animals from the east coast of North America have generally been classified as a single species, Crepidula plana Say, 1822. Based on allozyme and developmental data, however, Hoagland (K.E. Hoagland. 1984. Malacologia, 25: 607-628; K.E. Hoagland. 1986. Am. Malacol. Bull. 4: 173-183) concluded that two species of flat white-shelled Crepidula live along the east coast of the United States, but she did not apply any name to the second species. Herein I use molecular techniques to characterize populations of flat white-shelled Crepidula species from Texas, Florida, Georgia, North Carolina, and |Massachusetts, and describe their morphology and development. DNA-sequence data support the existence of three species. One species is readily distinguished on the basis of morphology and development, but the other two are very similar. To clarify the nomenclature of these species, I designate neotypes for C. plana Say, 1822 and Crepidula depressa Say, 1822, and describe Crepidula atrasolea sp.nov.

Assemblages and biogeography of demersal fishes of the east coast of North America

1998 ◽  
Vol 55 (7) ◽  
pp. 1704-1738 ◽  
Author(s):  
Robin Mahon ◽  
Stephen K Brown ◽  
Kees CT Zwanenburg ◽  
D Bruce Atkinson ◽  
Kenneth R Buja ◽  
...  
Keyword(s):  
North America ◽  
East Coast ◽  
Fish Assemblages ◽  
Single Species ◽  
Distribution Patterns ◽  
Demersal Fish ◽  
Trawl Survey ◽  
Distribution Maps ◽  
Cape Hatteras ◽  
Management Approaches

This study describes and maps demersal fish assemblages for the east coast of North America from Cape Hatteras, North Carolina, to Cape Chidley, Labrador, evaluates evidence for interannual shifts in assemblage distribution, and examines the relationship of the assemblages to accepted biogeographical boundaries. Demersal trawl survey data collected from 1975 to 1994 were analyzed. Visual classification of distribution maps for the 108 most abundant demersal species revealed nine species groups, based on both geography and depth distribution. Eighteen assemblage groups were identified using principal components analysis (PCA) and mapped. Assemblage groups were also identified by cluster analysis. Fish assemblages identified by both methods were spatially coherent. Assemblage distribution patterns were not consistent with accepted biogeographical boundaries. The PCA explained only 56.3% of the variance in distribution of the species, indicating that the assemblages should be interpreted as indeterminate, potentially adaptable entities rather than as rigid ecological constructs. Assemblages were persistent in composition through time but appeared to shift in location. The apparent looseness of the assemblages and their persistence through time in spite of severe impacts from fishing suggest that single-species management approaches may not be entirely inappropriate for the major groundfish species in the study area.

The Identification and Study of Indian Shell Middens in Eastern North America: 1643–1861

1986 ◽  
Vol 6 (3) ◽  
pp. 227-243 ◽  
Author(s):  
Andrew L. Christenson
Keyword(s):  
Nineteenth Century ◽  
Civil War ◽  
North America ◽  
East Coast ◽  
Eastern North America ◽  
Shell Midden ◽  
Shell Middens ◽  
Work Done

Although the interest in shell middens in North America is often traced to reports of the discoveries in Danish kjoekkenmoeddings in the mid-nineteenth century, extensive shell midden studies were already occurring on the East Coast by that time. This article reviews selected examples of this early work done by geologists and naturalists, which served as a foundation for shell midden studies by archaeologists after the Civil War.

SEA LEVEL BUDGET ALONG THE EAST COAST OF NORTH AMERICA

2017 ◽  
Author(s):  
Allison Pease ◽  
◽  
James Davis
Keyword(s):  
North America ◽  
Sea Level ◽  
East Coast

scholarly journals Topological and Morphological Controls on Morphodynamics of Salt Marsh Interiors

2021 ◽  
Vol 9 (3) ◽  
pp. 311
Author(s):  
Ben R. Evans ◽  
Iris Möller ◽  
Tom Spencer
Keyword(s):  
Salt Marsh ◽  
Salt Marshes ◽  
East Coast ◽  
Marsh Surface ◽  
Coastal Environments ◽  
Coastal System ◽  
Morphological Segmentation ◽  
The Usa ◽  
The Uk ◽  
Over Time

Salt marshes are important coastal environments and provide multiple benefits to society. They are considered to be declining in extent globally, including on the UK east coast. The dynamics and characteristics of interior parts of salt marsh systems are spatially variable and can fundamentally affect biotic distributions and the way in which the landscape delivers ecosystem services. It is therefore important to understand, and be able to predict, how these landscape configurations may evolve over time and where the greatest dynamism will occur. This study estimates morphodynamic changes in salt marsh areas for a regional domain over a multi-decadal timescale. We demonstrate at a landscape scale that relationships exist between the topology and morphology of a salt marsh and changes in its condition over time. We present an inherently scalable satellite-derived measure of change in marsh platform integrity that allows the monitoring of changes in marsh condition. We then demonstrate that easily derived geospatial and morphometric parameters can be used to determine the probability of marsh degradation. We draw comparisons with previous work conducted on the east coast of the USA, finding differences in marsh responses according to their position within the wider coastal system between the two regions, but relatively consistent in relation to the within-marsh situation. We describe the sub-pixel-scale marsh morphometry using a morphological segmentation algorithm applied to 25 cm-resolution maps of vegetated marsh surface. We also find strong relationships between morphometric indices and change in marsh platform integrity which allow for the inference of past dynamism but also suggest that current morphology may be predictive of future change. We thus provide insight into the factors governing marsh degradation that will assist the anticipation of adverse changes to the attributes and functions of these critical coastal environments and inform ongoing ecogeomorphic modelling developments.

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