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Freshwater bivalve shells may record inter-annual fluctuations in water chemistry, which in turn may archive variations in solute load due to pollution or discharge events. Here, using weekly surface water chemistry collected at two locations and shells of Lampsilis cardium grown in the surface water we investigate if the Mg/Ca, Mn/Ca, Sr/Ca, and Ba/Ca ratios measured at high resolution in the shells on an intra-annual time scale consistently reflect the chemistry of the surface water. Two relationships appear highly correlated, Sr/Cacarb and Sr/Cawater, and Mn/Cacarb and temperature. Ba/Cacarb correlated strongly with Ba/Cawater in one shell but temperature in another shell yielding inconclusive results. Mn/Cacarb and Mg/Cacarb were not strongly correlated with elemental ratios in the water, but Mn/Cacarb did show variable, weak to moderate correlation with pH. We found consistent partition coefficient (DMe) values between individual shell samples grown in the same water with mean DMg = 0.0006, DMn = 17, DBa = 0.13, and DSr = 0.176. Sr/Cacarb and Sr/Cawater exhibited the strongest, most consistent correlation with partitioning coefficients that were consistent with published values, suggesting Sr/Cacarb can be used as a proxy for Sr/Cawater in freshwater mussels.

Nondestructive, sublethal, and sensitive health monitoring tools are needed to assess the health of freshwater mussels (family Unionidae). Recent developments to standardize hemocyte characterization have assisted in the hematologic assessment of wild and captive freshwater mussels. In this study, preliminary baseline hematological reference ranges were established for wild mapleleaf mussels Quadrula quadrula (n = 14) and threeridge mussels Amblema plicata (n = 20) collected from the Muskingum River in Devola, Ohio. Mussels were collected from the wild, and hemolymph was sampled from each mussel in the field upon capture (baseline sample). They were then transported live to a propagation facility. Subsequent hemolymph samples were collected at 2 and 4 weeks and quarterly thereafter for 11 months following translocation. Hemocyte counts, hemocyte morphology, and hemolymph chemistry (Na+ , Cl- , Mg2+ , P3- , K+ , Ca2+ , glucose, alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase]) were measured from each sample on each sampling occasion. Hemocyte counts were consistently greater in Q. quadrula than in A. plicata following transfer to captivity. Baseline hemocyte morphology and hemolymph chemistry varied between species. This study provides a foundation of reference ranges for hemocyte characterization for Q. quadrula, and A. plicata and a preliminary understanding of how hemocyte character might be expected to change when wild mussels are translocated into captivity, and thus be a useful technique for monitoring the health of freshwater mussels.

Freshwater mussels are among the most endangered animals in North America. Although there are numerous state and federal programmes aimed at conserving them, knowledge of the effects of captivity and relocation remains limited. Metabolomic techniques were used to assess the physiological state of freshwater mussels (Amblema plicata) relocated from the Muskingum River in Ohio to a conservation facility and to another stream in Ohio. Haemolymph samples were taken from mussels in the Muskingum River (MUS group), the facility (CAP group), and Big Darby Creek (DAR group) in September 2012 (month 3 post-relocation), November 2012 (month 5), May 2013 (month 11), and August 2013 (month 14). Samples were analyzed by gas chromatography–mass spectrometry and liquid chromatography–mass spectrometry. In total, 95 biochemicals were identified during the 2012 sampling period and 104 biochemicals during the 2013 sampling period. Glucose and lipid metabolism remained similar among all groups. Differences between the MUS group and the CAP and DAR groups were observed in altered amino acid and nucleotide metabolism. The results are indicative of a general stress response, which is evident for a year post-relocation. Decreased levels of these metabolites are likely to be responsible for decreased growth rates and higher mortality often observed in relocated mussels.

Summary Freshwater mussels are a particularly imperilled group of aquatic organisms. To date, there is limited understanding of their dietary and nutritional subsidies, including those from both autochthonous (aquatic) and allochthonous (terrestrial) sources. The aim of this study was to evaluate the relative contributions of potential nutritional resources to mussel biomass using a Bayesian mixing model (MixSIAR) for (i) bulk suspended versus benthic organic matter (OM) pools, (ii) general autochthonous versus allochthonous OM sources and (iii) specific individual OM sources. Nutritional subsidies of five species of freshwater mussels were assessed using natural abundance stable isotopes (δ13C, δ15N, δ2H) and natural radiocarbon (Δ14C). The ranges for each of the four isotopes were similar across all species and sampling dates, and mussel δ13C and δ15N values were similar to those measured in previous studies. Despite relatively low variability in this study, species and temporal differences in mussel δ15N, δ2H and Δ14C values were generally significant (P

The Parachondria (Chondropomorus) complex in Hispaniola is reviewed. Nineteen species are recognized including eight new species: Parachondria anatolensis n. sp., Parachondria arcisensis n. sp., Parachondria daedalus n. sp., Parachondria heatheraikenae n. sp., Parachondria isabellinus n. sp., Parachondria muchai n. sp., Parachondria silvaticus n. sp., and Parachondria stigmosus n. sp. Distributional and habitat notes are given for additional taxa. Chondropoma marinum "Weinland" Reeve, 1863, is regarded as a nomen dubium. Chondropoma (Chondropomorus) moroni Bartsch, 1946, is reidentified as Crossepoma emilianum (Weinland, 1862). Chondropoma simplex Pfeiffer, 1852, regarded by Bartsch (1946) as a Chondropomorus, is considered a Chondropoma.

Wild-caught fishes were examined from the Muskingum River in southeastern Ohio for the prevalence of glochidial infestation. Weekly collections over a 24-hour period for one year yielded 22 fish species (2,097 individuals). Six species (27%) were infested with glochidia—channel catfish, freshwater drum, gizzard shad, orange-spotted sunfish, bluegill, and hybrid Morone. Infestations were found during the months of March through August, and no infested fish were found during the months of September through February. The month with the highest number of infested fish species was August, and the lowest number occurred in April. The percentage of all individuals infested with glochidia was very low, 2.5%, but was similar to that reported for other rivers and higher that reported for most lakes. The percentage of all fish species infested was lower than those reported for rivers but still greater than the results for lakes. The impounded study site seems to fall between a unregulated river and a lake i...

The decline of the freshwater mussel fauna of the Ohio River, U.S.A. is compared to the dates of service of the existing dams, the arrival of the exotic zebra mussel, and the presence of urban centers on the mainstem. Based upon historical records we know that most pools supported 20–50 species of mussels; today many have fewer than ten. The results presented here show a mixed effect of the dams on the mussel fauna, ranging from marked deleterious effects in Hannibal, McAlpine, and Smithland pools to comparatively little effect in pools such as Dashields, Greenup, and Markland. In nearly all cases, the most dramatic declines in mussels were associated with the arrival of zebra mussels in the Ohio River in 1991. Pools with significant urban centers often had a loss of diversity well before the construction of dams or the arrival of zebra mussels; these losses are attributed to water quality problems associated with urban centers. Mussel diversity has thus declined in the Ohio River as the result ...

Background: Freshwater mussels are among the most endangered taxa in North America and minimally invasive techniques to evaluate their health are needed. Objective: The objective of this study was to develop a standardized approach for identifying and enumerating the cellular components of freshwater mussel hemolymph. Methods: Hemocyte clumping, total hemocyte count, and hemocyte morphology were compared in untreated hemolymph or hemolymph treated with formalin, sodium citrate, sodium heparin, EDTA, water, or l-cysteine. Morphology was then used to categorize hemocytes and perform a 100-cell differential. Results: Treatment with formalin or >25 mg/mL l-cysteine reduced hemocyte clumping, although only formalin significantly increased the total hemocyte count. However, formalin also induced crenation that impaired hemocyte identification. Both EDTA and sodium citrate-induced hemocyte degranulation while sodium citrate and >40 mg/mL l-cysteine-induced cell lysis. Hemocytes could be categorized into 2 groups of granulocytes (eosinophilic or basophilic) and 2 groups of agranulocytes (large or small) for performing a cytologic differential. The differential was not significantly altered by anticoagulant treatments providing cell morphology was adequate for obtaining a differential. Eosinophilic granulocytes predominated (59%) with fewer large agranulocytes (27%) and basophilic granulocytes (13%). Small agranulocytes comprised 2% of the total population. Conclusions: No single treatment provided an optimal method to evaluate freshwater mussel hemolymph. Maximal hemocyte counts were obtained following formalin treatment. l-cysteine reduced clumping and maintained hemocyte morphology for performing a cytologic differential. These techniques provide a standardized approach for the hematologic evaluation of freshwater mussels.

We surveyed the mussel fauna of Twin Creek in southwest Ohio and examined its distribution relative to several selected environmental parameters. Unionid presence was determined with visual searches at 36 sites across 76 km in four counties. Fifteen species from the subfamilies Anodontinae, Ambleminae, and Lampsilinae were recorded, with nine species found alive at 17 of the 36 sites. Mussel species richness and species composition agree in general with historical studies of Twin Creek and other streams in the Great Miami River watershed, although some species have declined or been extirpated. The subfamily Ambleminae was almost completely missing from the area. The presence of three species only as dead and relic shells also may indicate a loss of species richness over the last few decades. Species richness values from Twin Creek were lower than for streams in central and northeastern Ohio.

Lampsiline bivalves typically are considered a tribe within the Unionidae (Ambleminae: Lampsilini), and they display extraordinary morphological adaptations for reproduction. Recent studies have weakly corroborated the monophyly of the Lampsilini, but evolutionary relationships within the tribe and its sister lineage have yet to be elucidated convincingly. However, these determinations are necessary to better understand the evolution of the spectacular morphological diversity present in lampsilines, as well as the specific circumstances surrounding the group's origin. To clarify these matters, phylogenetic analyses were carried out on 2,310 nucleotide and 770 amino acid position matrices containing sequences from five protein coding gene regions on the F and M mitochondrial genomes from 21 amblemine species. Nodal support values on the best Bayesian inference tree robustly confirm the monophyly of lampsilines and a clade containing the following well-supported relationships: (((lampsilines, Popenaias) Ple...

Seven new species of Abbottella and related taxa are described from Hispaniola: Abbottella calliotropis n. sp., Abbottella diadema n. sp., Abbottella dichroa n. sp., Abbottella nitens n. sp., Abbottella paradoxa n. sp., Abbottella tenebrosa n. sp., and Leiabbottella thompsoni n. sp. Distributional and habitat notes are given for additional taxa.

Terrestrial snail surveys were conducted at 1693 ha of reclaimed strip-mined land at The Wilds and at 3344 ha of woodland at the Shawnee Wilderness Area, both in Ohio, USA. These areas shared the same original physiography, vegetative cover, and soils prior to mining and are believed to have had the same land snail assemblages. The Wilds consisted of 37% woods and 63% open fields, both the result of reclamation activities. The Shawnee site was 3% fields and 97% woods. Fifty species were recorded from Shawnee and 60 from The Wilds. The older areas of woodlands and marginal new growth stands in The Wilds had recovered up to 55% of the presumed original woodland fauna based on shared assemblages with Shawnee. The fields at The Wilds were dominated by species that were rare at Shawnee. We hypothesize that these species were adapted to specialized but sparse microhabitats at Shawnee and were able to successfully colonize the disturbed areas (fields) at The Wilds when given the opportunity. As the fields at The Wilds yield to new growth woods these “field” species should return to their lower densities in the woodlands. The ranges of the original woodland species at The Wilds, now confined to the older growth woods, will expand as succession continues. If the woodlands are left to expand, then we expect the majority of the original land snail fauna will eventually return to The Wilds. However, the conversion of original woodlands at The Wilds to open fields during reclamation has complicated and slowed this recovery process. Fifty years after restoration began, The Wilds has not regained its original snail fauna.

We present a revised list of freshwater mussels (order Unionida, families Margaritiferidae and Unionidae) of the United States and Canada, incorporating changes in nomenclature and systematic taxonomy since publication of the most recent checklist in 1998. We recognize a total of 298 species in 55 genera in the families Margaritiferidae (one genus, five species) and Unionidae (54 genera, 293 species). We propose one change in the Margaritiferidae: the placement of the formerly monotypic genus Cumberlandia in the synonymy of Margaritifera. In the Unionidae, we recognize three new genera, elevate four genera from synonymy, and place three previously recognized genera in synonymy. We recognize for the first time two species (one native and one nonindigenous) in the Asian genus Sinanodonta as occurring in North America. We recognize four new species and one subspecies and elevate 21 species from synonymy. We elevate 10 subspecies to species status and no longer recognize four subspecies. We change common names for five taxa, correct spelling for eight species, and correct the date of publication of original descriptions for four species.

Twenty annulariid taxa are reviewed from Central America, including three new species and one new genus. One species is regarded as an incertae sedis and two as mislabeled lots of Cuban origin. Many species are highly endemic. Although not speciose, Central America has a high diversity of conchological forms and may represent the ancestral source of annulariids in general.

Effective conservation of freshwater mussels (Mollusca: Bivalvia: Unionidae), one of the most endangered groups of animals in North America, is compromised by limited knowledge of their health. We address this gap in knowledge by characterizing the metabolic profile of Amblema plicata in the wild and in response to captivity and food limitation. Eight mussels brought into captivity from the wild were isolated for 18 days without a food source. Hemolymph samples were taken prior to, and 9 and 18 days after the start of the experiment; these samples were analyzed by gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. We detected and identified 71 biochemicals in the hemolymph of freshwater mussels; of these, 49 showed significant changes during captivity and/or food limitation (p

Abstract A two-year government funded project is being conducted to evaluate the viability and applicability of Reverse-Circulation Primary Cementing (RCPC) in deepwater wells. This project focuses on the identification of technical issues that must be addressed before routine RCPC operations can occur in deepwater wells, and a recommended path forward to full evaluation of the viability of this placement technique in deepwater. Analysis includes numerical models and simulations, mechanical placement controls, cementing materials, and operational challenges. While RCPC has been used on land and on a few shallow water offshore wells, it has not yet been fully evaluated for use in a challenging deepwater environment. The application of RCPC to deepwater wells is expected to reduce bottom-hole circulating pressures and prevent lost circulation during cementing, as well as increase safety, environmental sustainability, zonal isolation, and improve cement seals. Standard commercially available software packages are unable to directly model the flow path through the complex configuration of a deepwater reverse-circulation cementing process. A multi-physics finite-element software package has been used to develop a model to predict temperatures and pressures during the reverse-circulation cementing process. Evaluation of mechanical placement controls has found that a major challenge will be the development of a switchable crossover between a conventional and reverse flow path, and the modification of float equipment. Also, with the application of RCPC it is anticipated that the design methodology of cementing fluids may be affected by changing the placement method. One major challenge in deepwater cementing is the narrow formation fracture gradient, so the application of RCPC has clear beneficial potential. By lowering the Equivalent Circulation Densities (ECDs) during the job, the risk of fracturing the formation and lost-circulation is decreased. Less fluid lost to the formation during placement can potentially lead to higher tops of cement (TOC) and improved cement bonding and zonal isolation.

The vertical migration patterns of eight freshwater mussel species were studied in outdoor enclosures. Individual experiments lasted from nine to 20 months, during which time mussels were observed three times per week. The mussels displayed two patterns of seasonal vertical migration; in both patterns populations of each species surfaced during spawning in spring and eventually reburied in autumn. These activities coincided with increasing spring water temperatures and decreasing autumn water temperatures, as well as increasing and decreasing durations of daylight. One group of species displayed a unimodal annual pattern, where most of the population surfaced in the spring and remained there until autumn. The second group displayed a bimodal pattern in which the population reburied itself after emerging in spring but then resurfaced and remained at the surface until autumn. We have not been able to associate this second emergence with any biological function. Patterns did not follow generic or su...

This study determined that inexpensive and easily maintained amphibians and exotic fishes could act as hosts for two species of native North American unionid mussels, and bypass the need to identify native hosts when the object is to culture mussels. Two mussel species, Lampsilis cardium and Utterbackia imbecillis, were used to parasitize 42 exotic fishes and seven potential nonpiscine host species. Nonpiscine hosts included amphibians and decapod crustaceans. Lampsilis cardium successfully metamorphosed on six species of exotic fishes, as well as on larval tiger salamanders. Utterbackia imbecillis successfully metamorphosed on 30 species of exotic fishes and all four amphibian species tested. No glochidia metamorphosed on crustaceans. Successful metamorphosis on amphibians indicates that mussel zoogeography may be more complicated than previously thought. Using surrogate hosts may be a valuable alternative to natural hosts in laboratory culture of mussels.

Larval tiger salamanders (Ambystoma tigrinum ssp.) were infected with glochidia of the freshwater mussel Lampsilis cardium in laboratory experiments. At 20–21 °C, metamorphosis occurred from 9 to 39 days, primarily between 9 and 17 days. The percentage of attached glochidia that metamorphosed varied from 0.27 to 15.7%. Metamorphosis on the salamanders occurred more quickly than on a known piscine host, largemouth bass (Micropterus salmoides), but a smaller percentage of the total attached glochidia metamorphosed. The role of amphibians as hosts of freshwater mussels in North America has not been addressed. Recognizing such a relationship could have important consequences for our understanding of mussel zoogeography.

The distributions of two unionoids (fragile papershell Leptodea fragilis and pink heelsplitter Potamilus alatus) were examined in five North American Midwest river systems in relation to the location of dams on the rivers. These dams were non-navigational (without locks), lacked fish ladders, and varied in height from 1 to 17·7 m. Both species were restricted in their distribution to the river downstream of the dams. This suggests that the host fish(es) of these species was unable to move upstream of these obstacles. Both unionoids are believed to parasitize the freshwater drum Aplodinotus grunniens. Several endangered unionoid species also may use this fish, or other dam-limited fishes, as hosts. Dams, even lowhead structures, may contribute to the overall depletion of unionoids by artificially restricting their distributions and isolating populations from each other. Management practices for endangered fishes and mussels must take into account these physical obstacles.

In recent years, drilling and production activity in US shale gas has been increasing. This high volume of work has led to the use of manufacturing-style well construction. Each area has its own challenges; however, problematic wells are prevalent in many shale plays. A major study in the Haynesville shale targeted the manufacturing-style methodology. Over the course of the study, more than 160 cement jobs were analyzed including surface, intermediate and production strings. This study implemented the use of careful engineering decisions that were focused on the issues and challenges specific to wells in this area. This was achieved through analyzing and optimizing the laboratory operations, design of cement systems, bulk plant and job site processes. This study shows by taking the proper steps to design these processes, a manufacturing style approach can be very successful when applied in challenging shale cementing operations.

A novel method for creating short, highly conductive fractures in wells to bypass formation damage has been developed. The method uses relatively small material volumes, low horsepower and pump rate, produces minimal environment effect, and leaves the formation face and proppant pack residue free. Function and application of the method present significant varia-tions in treatment design and execution compared to traditional hydraulic fracturing past damage. This paper presents results of development work to confirm the method’s applicability and to provide sufficient performance data to design initial field applications.

EGU06-A-06659; The Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) on the Mars Express orbiter obtained data over the North Polar Layered Deposits (NPLD)and found that they were easily penetrated to their base by the radar signal, and that the deposits must be nearly pure ice. In addition, there was no evidence for deflection of the lower contact of the NPLD with the substrate, implying a thick elastic lithosphere beneath that sector of the NPLD. Here we report on new MARSIS observations of the South Polar Layered Deposits (SPLD). The radar echoes from the surface of the SPLD are typically comparable in strength or weaker than those from surrounding smooth Mars surfaces. The signals clearly penetrate deep into the deposits at all frequency bands. In most cases, a strong reflection is seen at a time delay consistent with the expected depth of the contact of the SPLD materials with the substrate, as observed on the NPLD. Over the highest elevation SPLD surfaces, near 0° longitude, the estimated depth to the lower interface is about 3 km. In some areas, the lower interface is not clearly detected. Multiple internal interfaces are common. These can be quite continuous, over several 100 km in many cases. Some internal interfaces are substantially brighter than others, and some differences are seen in the apparent internal structure at different MARSIS frequencies. Certain regions observed multiple times consistently show a strong local brightening of the echo from the lower interface. Many areas show a gradual, rather than abrupt, decline in echo strength at time delays beyond the lower interface. Thin layered units off the main SPLD are also penetrated by MARSIS, with a second interface detected at their lower boundaries.

“The distribution in space of the uniones of the continental interior has been shown to be in many respects very peculiar” Keyes 1894:26.

Seven new species of Abbottella and related taxa are described from Hispaniola: Abbottella calliotropis n. sp., Abbottella diadema n. sp., Abbottella dichroa n. sp., Abbottella nitens n. sp., Abbottella paradoxa n. sp., Abbottella tenebrosa n. sp., and Leiabbottella thompsoni n. sp. Distributional and habitat notes are given for additional taxa.

International audience; The MARSIS radar sounder on Mars Express completed a comprehensive mapping campaign of the south polar region. The radar signal typically penetrates to the base of the layered deposits. Terrain outside of the classic layered deposits also exhibits layering in the radar data.