Research priorities for freshwater mussel conservation assessment

Freshwater mussels are declining globally, and effective conservation requires prioritizing research and actions to identify and mitigate threats impacting mussel species. Conservation priorities vary widely, ranging from preventing imminent extinction to maintaining abundant populations. Here, we develop a portfolio of priority research topics for freshwater mussel conservation assessment. To address these topics, we group research priorities into two categories: intrinsic or extrinsic factors. Intrinsic factors are indicators of organismal or population status, while extrinsic factors encompass environmental variables and threats. An understanding of intrinsic factors is useful in monitoring, and of extrinsic factors are important to understand ongoing and potential impacts on conservation status. This dual approach can guide conservation status assessments prior to the establishment of priority species and implementation of conservation management actions.NF-R was supported by a post-doctoral fellowship (Xunta de Galicia Plan I2C 2017-2020, 09.40.561B.444.0) from the government of the autonomous community of Galicia. BY was supported by the Ministry of Science and Higher Education (no. 0409-2016-0022). DLS was supported by the G. E. Hutchinson Chair at the Cary Institute of Ecosystem Studies. AO was supported by the Russian Foundation for Basic Research (no. 17-44-290016). SV was funded by European Investment Funds by FEDER/COMPETE/POCI- Operacional Competitiveness and Internacionalization Programme, under Project POCI-01-0145-FEDER-006958 and National Funds by FCT-Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2013. NF-R is very grateful to the University of Oklahoma Biological Survey for providing space to work in the U.S. and especially to Vaughn Lab members. Authors are very grateful to Akimasa Hattori, Allan K. Smith, Andrew Roberts, Daniel Graf, David Stagliano, David T. Zanatta, Dirk Van Damme, Ekaterina Konopleva, Emilie Blevins, Ethan Nedeau, Frankie Thielen, Gregory Cope, Heinrich Vicentini, Hugh Jones, Htilya Sereflisan, Ilya Vikhrev, John Pfeiffer, Karen Mock, Mary Seddon, Katharina Stockl, Katarzyna Zajac, Kengo Ito, Marie Capoulade, Marko Kangas, Michael Lange, Mike Davis, Pirkko-Liisa Luhta, Sarina Jepsen, Somsak Panha, Stephen McMurray, G. Thomas Watters, Wendell R. Haag, and Yoko Inui for their valuable contribution in the initial selection and description of extrinsic and intrinsic factors. We also wish to thank Dr. Amanda Bates, Chase Smith, and two anonymous reviewers for comments on earlier drafts of this manuscript. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government

The conservation status of the world's freshwater molluscs

With the biodiversity crisis continuing unchecked, we need to establish levels and drivers of extinction risk, and reassessments over time, to effectively allocate conservation resources and track progress towards global conservation targets. Given that threat appears particularly high in freshwaters, we assessed the extinction risk of 1428 randomly selected freshwater molluscs using the IUCN Red List Categories and Criteria, as part of the Sampled Red List Index project. We show that close to one-third of species in our sample are estimated to be threatened with extinction, with highest levels of threat in the Nearctic, Palearctic and Australasia and among gastropods. Threat levels were higher in lotic than lentic systems. Pollution (chemical and physical) and the modification of natural systems (e.g. through damming and water abstraction) were the most frequently reported threats to freshwater molluscs, with some regional variation. Given that we found little spatial congruence between species richness patterns of freshwater molluscs and other freshwater taxa, apart from crayfish, new additional conservation priority areas emerged from our study. We discuss the implications of our findings for freshwater mollusc conservation, the adequacy of a sampled approach and important next steps to estimate trends in freshwater mollusc extinction risk over time

Annotated type catalogue of lymnaeid snails (Mollusca, Gastropoda) in the collection of the Natural History Museum, Berlin

The article deals with examination of the type materials of sixty-one species and variety of lymnaeid snails (Mollusca: Gastropoda: Lymnaeidae) housed in molluscan collection of the Natural History Museum Berlin, Germany (ZMB). Each taxon is discussed following the same scheme, including synomymy, information on the type materials, current taxonomic allocation, taxonomic and nomenclatorial remarks

Conceptual shifts in animal systematics as reflected in the taxonomic history of a common aquatic snail species (Lymnaea stagnalis)

Lymnaea stagnalis (L., 1758) is among the most widespread and well-studied species of freshwater Mollusca of the northern hemisphere. It is also notoriously known for its huge conchological variability. The history of scientific exploration of this species may be traced back to the end of the 16th century (Ulisse Aldrovandi in Renaissance Italy) and, thus, L. stagnalis has been chosen as a proper model taxon to demonstrate how changes in theoretical foundations and methodology of animal taxonomy have been reflected in the practice of classification of a particular taxon, especially on the intraspecific level. In this paper, I depict the long story of recognition of L. stagnalis by naturalists and biologists since the 16th century up to the present day. It is shown that different taxonomic philosophies (essentialism, population thinking, tree thinking) led to different views on the species’ internal structure and its systematic position itself. The problem of how to deal with intraspecific variability in the taxonomic arrangement of L. stagnalis has been a central problem that made systematists change their opinion following conceptual shifts in taxonomic theory

Ladislavella occulta (Jackiewicz, 1959) – a species of aquatic snails new for Hungary with remarks on its distribution in Central and Eastern Europe

Vinarski, Maxim V. (2020): Ladislavella Occulta (Jackiewicz, 1959) - A Species Of Aquatic Snails New For Hungary With Remarks On Its Distribution In Central And Eastern Europe. Acta Zoologica Academiae Scientiarum Hungaricae 66 (4): 369-377, DOI: 10.17109/AZH.66.4.369.2020, URL: http://dx.doi.org/10.17109/azh.66.4.369.202

An annotated catalogue of the gamasid mites associated with small mammals in Asiatic Russia. The family Laelapidae s. str. (Acari: Mesostigmata: Gamasina)

Vinarski, Maxim V., Korallo-Vinarskaya, Natalia P. (2016): An annotated catalogue of the gamasid mites associated with small mammals in Asiatic Russia. The family Laelapidae s. str. (Acari: Mesostigmata: Gamasina). Zootaxa 4111 (3): 223-245, DOI: http://doi.org/10.11646/zootaxa.4111.3.

Gyraulus elenae sp. n. — a new Planorbid snail from Eastern Turkey (Mollusca: Gastropoda: Planorbidae)

Vinarski, Maxim V., Glöer, Peter, Palatov, Dmitry M. (2013): Gyraulus elenae sp. n. — a new Planorbid snail from Eastern Turkey (Mollusca: Gastropoda: Planorbidae). Zootaxa 3664 (1): 95-98, DOI: 10.11646/zootaxa.3664.1.

Taxonomic assessment of genetically-delineated species of radicine snails (Mollusca, Gastropoda, Lymnaeidae)

The article represents an overview of 29 biological species of the radicine snails (genera Ampullaceana Servain, 1882, Bullastra Bergh, 1901, Racesina Vinarski & Bolotov, 2018, Kamtschaticana Kruglov & Starobogatov, 1984, Myxas G.B. Sowerby I, 1822, Orientogalba Kruglov & Starobogatov, 1985; Peregriana Servain, 1882, Radix Montfort, 1810, and Tibetoradix Bolotov, Vinarski & Aksenova, 2018) recovered during our previous molecular taxonomic study (Aksenova et al. 2018a; Scientific Reports, 8: 11199). For each species, the following information is provided: scientific name, a (non-exhaustive) list of synonyms, type locality, type materials, shell and copulative apparatus morphology, distribution, and nomenclatural and taxonomic remarks. The colour images of shell(s) of each species are also given as well as illustrations of the copulatory apparatuses. We revealed a great conchological variation in the radicines, both intra- and interspecific, alongside with striking uniformity in the structure of their copulatory apparatuses. The latter was once thought to be a reliable tool for species delineation and identification in this snail group. The total of 29 species characterised here represents, probably, only a subset of the global taxonomic richness of the radicine snails, which approaches 50 species

Ixodes apronophorus Schulze (Acari: Ixodida: Ixodidae): Distribution, Abundance, and Diversity of Its Mammal Hosts in West Siberia (Results of a 54-Year Long Surveillance)

Ixodes apronophorus Schulze, 1924, the marsh tick, belongs to a group of so-called “neglected” ixodid ticks, which remain underexplored compared to the most well-studied species of the genus Ixodes (I. ricinus, I. persulcatus). In this communication, we analyze and summarize the quantitative data on the abundance of this parasite, its geographical distribution, and the diversity of its small mammal hosts in the region of West Siberia (Asiatic Russia). The analyzed data represent a continuous series of observations made between 1953 and 2007, which constitutes one of the longest timeseries ever studied by acarologists. It is shown that the marsh tick in West Siberia is most common in the northern forest steppe and southern taiga landscape zones, being distributed south of 60° N. Among 24 species of small mammals registered as hosts for I. apronophorus in the studied region, three play the most important role: the European water vole (Arvicola amphibius), the tundra vole (Microtus oeconomus), and the Northern red-backed vole (Clethrionomys rutilus). The data characterizing parasitism of the marsh tick on these three hosts in various landscape zones and subzones are provided. We can report a weak albeit significant negative relationship between the abundances of I. apronophorus and its small mammal hosts. The possible explanation lies in the mismatch between the cycles of abundance characteristic of the tick and its hosts