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1.  Eutrophication and Dreissena Invasion as Drivers of Biodiversity: A Century of Change in the Mollusc Community of Oneida Lake 
PLoS ONE  2014;9(7):e101388.
Changes in nutrient loading and invasive species are among the strongest human-driven disturbances in freshwater ecosystems, but our knowledge on how they affect the biodiversity of lakes is still limited. We conducted a detailed historical analysis of the mollusc community of Oneida Lake based on our comprehensive lakewide study in 2012 and previous surveys dating back to 1915. In the early 20th century, the lake had a high water clarity, with abundant macrophytes and benthic algae, and hosted the most diverse molluscan community in New York State, including 32 gastropod and 9 unionid species. By the 1960s, lake turbidity increased during a period of anthropogenic eutrophication, resulting in a 38% decline in species richness and a 95% reduction in abundance of native gastropods grazing on benthic algae. Following the invasion of Dreissena spp. in 1991 and subsequent increases in water clarity, native gastropod species richness expanded by 37% and abundance increased 20-fold by 2012. In contrast, filter-feeding unionids were unaffected by increased turbidity during the period of eutrophication but were extirpated by dreissenids. Through contrasting effects on turbidity, eutrophication and Dreissena spp. have likely driven the observed changes in native grazing gastropods by affecting the abundance of light-limited benthic algae. Given the high species richness and ecological importance of benthic grazers, monitoring and managing turbidity is important in preserving molluscan diversity.
doi:10.1371/journal.pone.0101388
PMCID: PMC4092058  PMID: 25010705
2.  Distribution, genetic analysis and conservation priorities for rare Texas freshwater molluscs in the genera Fusconaia and Pleurobema (Bivalvia: Unionidae) 
Aquatic Biosystems  2012;8:12.
Background
Freshwater bivalves in the order Unionoida are considered to be one of the most endangered groups of animals in North America. In Texas, where over 60% of unionids are rare or very rare, 15 species have been recently added to the state’s list of threatened species, and 11 are under consideration for federal listing. Due to insufficient survey efforts in the past decades, however, primary data on current distribution and habitat requirement for most of these rare species are lacking, thus challenging their protection and management. Taxonomic identification of endemic species based on shell morphology is challenging and complicates conservation efforts. In this paper we present historic and current distributional data for three rare Texas species, Fusconaia askewi, F. lananensis, and Pleurobema riddellii, collected during our 2003–2011 state-wide surveys and suggest appropriate conservation measures. In addition, we tested the genetic affinities of Fusconaia and similar species collected from eastern Texas and western Louisiana using cox1 and nad1 sequences.
Results
We found that F. askewi still inhabits four river basins in eastern and northeastern Texas and can be locally abundant, while P. riddellii was found only in one river basin. Pleurobema riddellii was well-separated from F. askewi and grouped with the P. sintoxia clade. The sequences for F. lananensis were very similar to those for F. askewi, with a maximum difference of just over 1% for nad1 and only 0.7% for cox1, similar to the variation between F. askewi alleles. Except for one low difference (1.55%) with the partial cox1 sequence for F. burkei, all other Fusconaia populations, including those from the Calcasieu drainage, differed by over 2.3% for both genes.
Conclusions
Our study suggested that F. lananensis is not a valid species, and it is likely that only one Fusconaia species (F. askewi or its probable senior synonym F. chunii) is currently present in East Texas, thus simplifying conservation efforts. Distribution range of both these regional endemics (F. askewi and P. riddellii) has been reduced in the last 80 years.
doi:10.1186/2046-9063-8-12
PMCID: PMC3422191  PMID: 22731520
Freshwater molluscs; Fusconaia askewi; Fusconaia lananensis; Pleurobema riddellii; Molecular identification; Taxonomy; Distribution; Habitat requirements; Conservation priorities

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