Open research questions in Aquatic Invertebrate Ecology and Behavior

What the literature leaves open

• The researchers had to deal with the unclear taxonomic identity of R. subdisjuncta. The study required the examination of type series and paratypes of Radix species, which can be a challenging task.

  The Pond Snails of the Genus Radix (Gastropoda, Lymnaeidae) in Issyk-Kul Lake (Central Asia), with a Review of Radix in Ancient Tectonic Lakes of the World · 2025 · DOI

• The application of species distribution models to reconstructing past distributions is less common. There is a lack of understanding of the distinct ecologies of U. crassus and U. nanus for conservation. The study of historical distribution is important for interpreting phylogeography and current genetic patterns but is often overlooked.

  Environmental Niche Differentiation and Past Colonization Dynamics of Two European Freshwater Mussels (Unio crassus and Unio nanus) · 2025 · DOI

• The dynamics of gut bacterial communities in freshwater mussels at different life stages are still limited. There is a lack of understanding of the stage-specific taxonomic profiles of gut bacterial communities in freshwater mussels.

  Comparison of Gut Bacterial Communities in the Freshwater Mussel Sinanodonta woodiana at Different Life Stages · 2025 · DOI

• There is a lack of baseline data on the current distribution and life history traits of S. ambigua in Ontario, Canada. There are knowledge gaps associated with aspects of S. ambigua life history, including reproductive timing and host infestation period.

  Status and Life History Traits of Simpsonaias ambigua (Salamander Mussel) in Ontario, Canada · 2025 · DOI

• The paper identifies a need to describe and analyse the present Swedish fauna of freshwater snails. It highlights the importance of understanding the species' zoogeography, ecology, and conservation status.

  The Swedish Fauna of Freshwater Snails—An Overview of Zoogeography and Habitat Selection with Special Attention to Red-Listed Species · 2025 · DOI

• There is a need to assess the correlations between biological factors and bivalve distribution. The study aims to evaluate the community-level diversity characteristics of freshwater bivalves across sites.

  Diversity Patterns and Environmental Drivers of Bivalve Communities in the Caizi Lake Group and Its Major Tributaries During the Initial Post-Fishing Ban Period · 2025 · DOI

• There is a lack of knowledge on the recruitment potential of Pinna nobilis. The factors influencing the growth and survival of juveniles are not well understood. There is a need for effective methods to enhance recruitment and conservation of the species.

  Recruitment and Controlled Growth of Juveniles of the Critically Endangered Fan Mussel Pinna nobilis in the Northern Adriatic · 2025 · DOI

• The paper highlights the need for databasing and preserving private collections.

  Herbert D. Athearn and the Museum of Fluviatile Mollusks · 2025 · DOI

• The morphological characteristics of the shell and soft body parts can overlap and vary based on the age and size of a particular specimen. The identification of endangered species may still need to rely on molecular methods. Classification errors occurred for some species, with the model predicting that they can be confused with other species.

  The Quantification of Morphological Variation and Development of Morphology-Based Keys to Identify Species of Fusconaia and Pleurobema (Unionidae) in the Green River, Kentucky, USA · 2025 · DOI

• The lack of a comprehensive understanding of the morphological variation among Fusconaia and Pleurobema species. The need for a reliable method for identifying these species in the field.

  The Quantification of Morphological Variation and Development of Morphology-Based Keys to Identify Species of Fusconaia and Pleurobema (Unionidae) in the Green River, Kentucky, USA · 2025 · DOI

• Further research is needed to understand the factors affecting recruitment and growth of P. nobilis, - Studies on the long-term effects of different maintenance systems on P. nobilis growth and survival are needed, - Research on the impact of sea temperature on P.

  Recruitment and Controlled Growth of Juveniles of the Critically Endangered Fan Mussel Pinna nobilis in the Northern Adriatic · 2025 · DOI

• Globally, freshwater mussels are facing severe declines, yet their nutritional ecology and its link to catchment land‐use pressures remain poorly understood.

  Environmental Effects on the Selective Feeding and Fatty Acid Retention of Freshwater Pearl Mussel · 2026 · DOI

• Biological invasions have become a major component of global change, yet the processes governing secondary spread after initial introductions remain insufficiently resolved.

  Quantifying Colonisation Pressure as a Driver of Secondary Spread During the Dreissena polymorpha Invasion of German River Networks · 2026 · DOI

• The taxonomic position of Radix species in Issyk-Kul Lake is not well understood. There is a lack of molecular evidence for the presence of R. obliquata outside Issyk-Kul Lake. The study aims to fill this gap by providing a revision of the genus Radix.

  The Pond Snails of the Genus Radix (Gastropoda, Lymnaeidae) in Issyk-Kul Lake (Central Asia), with a Review of Radix in Ancient Tectonic Lakes of the World · 2025 · DOI

• This includes the freshwater mussel genus Nodularia, endemic to East Asia, for which a comprehensive understanding of species diversity and phylogenetic relationships remains elusive due to inadequate sampling in previous studies, particularly in China, a widely recognized biodiversity hotspot for freshwater mussels.

  Diversity, morphology, and phylogeny of freshwater mussels of the genus Nodularia (Bivalvia: Unionidae) from China, with descriptions of four new species · 2024 · DOI

• The freshwater mussels (Bivalvia: Unionida) of the biodiversity hotspot Sundaland are experiencing severe anthropogenic threats, whilst their diversity and distribution remain poorly understood.

  High endemic freshwater mussel (Bivalvia: Unionida) diversity in western Borneo, with description of three new species · 2024 · DOI

• Dreissenids and Diporeia interact with their environment in fundamentally different ways, and the consequences of this functional shift in benthic community structure on benthic–pelagic coupling are not well understood, particularly in unproductive offshore lake regions.

  Invasive mussels reduce community bioturbation but do not affect oxygen penetration or nutrient fluxes in organic‐poor Great Lakes sediments · 2024 · DOI

• The study highlights the need for increased sampling in future research on Ellobiidae. The absence of tRNA-Ser in Ellobiidae was noted, but the reason for this is unclear.

  Phylogenetic Relationships Within Ellobiidae (Gastropoda: Eupulmonata) Based on Complete Mitochondrial Genomes: New Insights and Taxonomic Implications · 2026 · DOI

• The use of 3D-printed mussels as a surrogate for live mussels has limitations, including the lack of behavioral response to stress events. Potential plastic pollution is a concern.

  Addendum: Assessing suitable habitat for freshwater mussel reintroductions using 3D-printed subadultreplicates · 2026 · DOI

• The research gap is the lack of understanding of the limitations of using 3D-printed mussels as a surrogate for live mussels. The gap is addressed by comparing the mobilization thresholds of 3D-printed and live subadult mussels.

  Addendum: Assessing suitable habitat for freshwater mussel reintroductions using 3D-printed subadultreplicates · 2026 · DOI

• The study does not consider other potential negative consequences of zebra mussel invasions, such as on water treatment facilities. The study uses data from a limited number of reservoirs (25) and a limited time period (2 decades).

  Two decades of zebra mussel (Dreissena polymorpha) invasion in Kansas reservoirs have minimal effects on water quality and fish communities · 2026 · DOI

• The lack of a comprehensive framework to predict the establishment of invasive species. The conflicting evidence from empirical studies.

  Dark diversity framework reconciles Darwin’s naturalization conundrum for freshwater fish invasions · 2026 · DOI

• Further studies can apply the dark diversity framework to other ecosystems and species. Research can focus on the development of more accurate models for predicting invasion outcomes.

  Dark diversity framework reconciles Darwin’s naturalization conundrum for freshwater fish invasions · 2026 · DOI

• Balancing the needs of sustainable mussel farming with the environmental constraints of the Maliakos Gulf. Managing the effects of nutrient inputs and water quality on mussel growth and settlement. Developing effective strategies for area- and season-specific management of spat collectors.

  Recruitment, Spat Settlement and Growth of the Cultured Mediterranean Mussel Mytilus galloprovincialis in the Maliakos Gulf (Central Aegean Sea) · 2025 · DOI

• No reproductive sampling occurred after October, - The study was conducted in a limited geographic area, - The sample size was relatively…

  Status and Life History Traits of Simpsonaias ambigua (Salamander Mussel) in Ontario, Canada · 2025 · DOI

Most-cited papers in Aquatic Invertebrate Ecology and Behavior

• Transformation of Freshwater Ecosystems by Bivalves · BioScience · 1999 · 436 citations
• Changing Perspectives on Pearly Mussels, North America's Most Imperiled Animals · BioScience · 2004 · 374 citations
• Catastrophic Change in Species-Rich Freshwater Ecosystems · BioScience · 1992 · 310 citations
• Do Reservoirs Facilitate Invasions into Landscapes? · BioScience · 2005 · 294 citations
• Biodiversity Losses and Ecosystem Function in Freshwaters: Emerging Conclusions and Research Directions · BioScience · 2010 · 282 citations
• Impact of the Zebra Mussel, a Bivalve Invader · BioScience · 1993 · 146 citations
• Allee Effects and the Risk of Biological Invasion · Risk Analysis · 2004 · 117 citations
• Freshwater Megafauna: Flagships for Freshwater Biodiversity under Threat · BioScience · 2017 · 94 citations
• The Future of Baltic Sea Populations: Local Extinction or Evolutionary Rescue? · AMBIO · 2011 · 84 citations
• The Threat of Climate Change to Freshwater Pearl Mussel Populations · AMBIO · 2003 · 81 citations

Most recent work

• Multi-endpoint ecophysiological indicators to assess freshwater mussel translocation success · Ecological Indicators · 2026
• An Urgent Call for the Coordinated Monitoring of European Freshwater Mussels · Conservation Letters · 2026
• Blooms like it hot, but mussels do not: Influence of invasive quagga mussels on cyanobacteria during summer · Harmful Algae · 2026
• Fish invasion restructures freshwater food webs, facilitating new invasions over three decades · Frontiers in Environmental Science · 2026
• A diverse satellite DNA repertoire in Limnoperna fortunei: insights into genome structure and chromosomal organization · Frontiers in Molecular Biosciences · 2026
• Freshwater Molluscan Assemblages in Upper Reaches of the Chi River, North-Eastern Thailand and Its Relationship of Physicochemical Habitat · Diversity · 2026
• Alien Chinese pond mussels (Unionidae, Sinanodonta) in Russia: new records, the stages of the invasion, and its current status · Hydrobiologia · 2026
• DNA barcoding and morphology reveal a broad distribution of Asian freshwater clams Corbicula fluminea and C. leana (Cyrenidae) in Vietnam · Ecologica Montenegrina · 2026
• An overlooked genus-level clade illuminates the origin and tectonic-driven diversification of a freshwater radiation in Asian mytiloid mussels (Bivalvia: Mytiloidea: Modiolidae) · Zoological Journal of the Linnean Society · 2026
• The silent replacement: reproductive failure and metabolic constraints drive the displacement of native freshwater snails under thermal stress · Biodiversity and Conservation · 2026

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