First record of Sinanodonta woodiana and report for freshwater bivalves from Iraq (Mollusca: Bivalvia: Unionidae)

Freshwater mussels (Mollusca: Bivalvia: Unionida) have a broad global distribution on every continent except Antarctica. However, owing to human activities, the diversity of freshwater mussels is seriously globally threatened. China is an important global biodiversity hotspot for this fauna. This article comprehensively reviews the 99 currently recognized species in China, collating for the first time their systematics, distribution, life‐history traits, habitat preferences, conservation status, and main threats to suggest future management actions. The review showed that the taxonomic status and species validity of many freshwater mussels are still not well resolved. The freshwater mussel diversity in the Yangtze River Basin is higher than that in other freshwater habitats in China. Life history characteristics and habitat preferences are poorly known for most species. Only half of the total number of species in China have been assessed for their conservation status. Among those assessed, around half of them are threatened with extinction with more than 10% being considered as Data Deficient. The key threats identified as potentially related to species declines are pollution, habitat loss and fragmentation, loss of access to host fishes and overharvesting of mussels or their host fishes. The review shows that there is a strong geographical bias in the amount of knowledge available for freshwater mussels, with most of the available data being concentrated in the middle and lower reaches of the Yangtze basin. Almost no data are available for these taxa north of the Yellow River basin and in the west and south‐west regions of China. To make future conservation and management more effective we suggest that efforts should be concentrated on: (i) increasing the amount of research on basic ecological and life‐history features, including growth, life‐span, reproductive cycle, host fish identification and habitat requirements of each species; (ii) establishing the interspecific and intraspecific genetic diversity patterns of Chinese freshwater mussels, to clarify their taxonomy, systematics and phylogeny, and to understand the phylogeography and population structure of each species; and (iii) urgently establishing protected areas for fish and mussels in locations of high species richness, such as Poyang Lake and Dongting Lake, and also in regions with high levels of endemism or genetic uniqueness, such as Guangxi Province, Yunnan Province and Heilongjiang Province. In addition, the need for habitat restoration and the conservation of freshwater mussels has become urgent in China, and an integrated systematic conservation and management plan should be developed and effectively implemented.

Section: Diversity and Taxonomymentioning

confidence: 99%

Systematics, distribution, biology, and conservation of freshwater mussels (Bivalvia: Unionida) in China

Liu

Wü

et al. 2022

“…There is no doubt that the invasion of this Nearctic species to the wetlands of Iraq is virtually impossible owing to its preference for colder water, oligotrophic environments of the Pacific Coast and Rocky Mountains (Blevins et al, 2017). Hence, this record is here considered as a misidentification of a native species, Leguminaia wheatleyi (Bogan et al, 2021), the general shell appearance of which looks rather similar to that of G. angulata . In addition, Jawad (2021) in their checklist erroneously placed Anodonta vescoiana in the Neotropical family Mycetopodidae, whereas this species belongs to the Unionidae (Bogan et al, 2021; Graf & Cummings, 2021).…”

Section: Resultsmentioning

confidence: 99%

“…Five native and one invasive freshwater mussel species have been recorded from Iraq (Alwanzadegan et al, 2023; Bogan et al, 2021). In a comprehensive book entitled Southern Iraq's marshes: their environment and conservation , Jawad (2021) listed one more species, Gonidea angulata (Unionidae), as a member of the regional fauna (Appendix ).…”

Section: Resultsmentioning

confidence: 99%

An alarming tendency towards freshwater mussel misidentification in scientific works may bias endangered and invasive species management

Bolotov,

Konopleva,

Vikhrev

et al. 2024

Freshwater mussels (order Unionida) are a popular group for a wide array of non‐taxonomic research driven by questions related to their functions in ecosystems, to relationships among species, to biogeochemical and morphometric patterns of certain species and others. Valid taxonomy and correct species identification are key requirements for all of these aspects. However, species‐level identification of representatives from this group is a rather complicated task and should be based on an integrative approach, combining DNA sequences, morphological and anatomical investigation and biogeographical estimates. This article reconsiders a selection of non‐taxonomic scientific works (N = 25), containing misidentified occurrences of freshwater mussel species. The dataset contains records of the endangered Margaritifera margaritifera (endemic to eastern North America and Europe) from the Philippines and West Africa, as well as occurrences of the Nearctic Gonidea angulata from West Africa and the Middle East. Several Palearctic and Nearctic unionid species were erroneously reported from the Indus River, Pakistan. Subfossil shells of the native Simpsonella sp. from a prehistoric site in the Philippines were misidentified as the invasive Sinanodonta woodiana that was introduced to the islands in the 20th century. Samples of the tropical lineage of S. woodiana from Indonesia were mistaken for the native Pilsbryoconcha exilis, and vice versa. Salinity tolerance and morphometric characteristics of the estuarine clam Geloina sp. (Cyrenidae) from Sumatra were examined, but these data were published as belonging to the strictly freshwater S. woodiana. It is clear that this information, being reused by researchers, conservationists and stakeholders, will lead to incorrect conclusions on the range, status, biogeochemistry, morphometry and ecological tolerance of certain freshwater mussel taxa, including invasive and endangered species (the so‐called ‘error cascades’ in biological sciences caused by ‘bad taxonomy’). To reduce the growing body of literature containing misidentifications of the Unionida taxa, practical recommendations are proposed for researchers, who include freshwater mussels in non‐taxonomic surveys, as well as for journal editors dealing with articles that focus on these animals.

“…Whereas the two other invasive species represent separate phylogenetic clades, they are currently linked to a single nominal taxon, S. woodiana (Bolotov et al, 2016). To delineate these species in the absence of an appropriate taxonomic revision, the use of informal names such as the temperate and the tropical invasive lineages of S. woodiana was proposed (Bolotov et al, 2016) that was generally accepted by subsequent researchers (Vikhrev et al, 2017;Konečný et al, 2018;Zieritz et al, 2018c;Kondakov et al, 2020;Bauer et al, 2021;Bogan, Al-Fanharawi & Lopes-Lima, 2021).…”

Section: S Lauta (Martens 1877) Has Established Non-native Population...mentioning

confidence: 99%

A riverine biodiversity hotspot in northern Myanmar supports three new and narrowly endemic freshwater mussel species

Bolotov

Konopleva

Chan³

et al. 2022

1. The Western Indochina Subregion (Myanmar) represents a freshwater biodiversity hotspot of worldwide significance and houses a plethora of endemic freshwater species, among which are amphibians, fish, and various aquatic invertebrates.2. The freshwater mussel (Bivalvia: Unionidae) fauna of western Indochina is characterized by high taxonomic richness, with almost all species and several genera being endemic to the subregion. Furthermore, there are a number of species endemic to a single basin or even to a single tributary of a larger river system (the so-called intra-basin endemic taxa). 3. Here, the discovery of three new, narrowly endemic freshwater mussel species from northern Myanmar is presented: Radiatula kachinensis sp. nov., Trapezidens mogaungensis sp. nov. (upper Ayeyarwady basin), and Lamellidens chindwinensis sp. nov. (upper Chindwin basin). All the new species are upland river specialists, which are under high human pressure as a result of habitat degradation, deforestation, oil palm expansion, river damming, and biological invasions. 4. A nearly complete lack of data on the life cycles and fish hosts should be considered the most striking gap in recent knowledge of tropical Asian freshwater mussels. Here, available data on 27 species belonging to the genera Radiatula, Trapezidens, and Lamellidens are revised. It is shown that certain fish hosts are known for two species only. 5. Further spread of the alien Chinese pond mussels (Sinanodonta woodiana species complex) in Indochina may be considered one of the significant threats to native freshwater mussel populations. Here, it is shown that the temperate invasive lineage of S. woodiana is established in at least three non-native populations in the Ayeyarwady and Salween basins. Moreover, the first arrival of the tropical invasive lineage of S. woodiana to Myanmar is announced, although it has been predicted previously. This lineage was found at two sites on the Shan Plateau (Ayeyarwady basin) close to the Chinese border.