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Coastal estuaries are especially vulnerable to the arrival and establishment of invasive aquatic species (IAS) as they are often the receiving locations of ship-based introductions. Rapid response tools, such as mechanical or chemical treatments to capture, remove, and contain of IAS, are needed to prevent subsequent spread into adjacent marine and freshwater systems. Abrupt salinity change, created when infrastructure in estuaries situated at the proximity of river mouths is operated, offers a novel, low-cost and environmentally friendly method for potentially controlling IAS. We investigated the use of osmotic shock to control the invasive brackish water clam Rangia cuneata that is quickly spreading through Europe. Clams were exposed in the laboratory to eight salinity concentrations ranging from 0.5 to 32.0‰ and monitored for 60 days. Saline shock, but not freshwater shock, could control R. cuneata. Salinities >26‰ killed 95% R. cuneata in two weeks. All specimens exposed to full strength seawater (32‰) were killed within 30 days. At lower salinities, clams collected from the most freshwater locality (1.2‰) showed lower mortality than clams from the most saline site (3.1‰). Furthermore, even modest increases in salinity during spawning periods of R. cuneata may prevent recruitment. Given the vulnerability of coastal estuaries to introduction of IAS, saline flushing presents a novel and effective management tool for many species., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Two Unionida (freshwater mussel) families are present in the Northern Hemisphere; the Margaritiferidae, representing the most threatened of unionid families, and the Unionidae, which include several genera of unresolved taxonomic placement. The recent reassignment of the poorly studied Lamprotula rochechouartii from the Unionidae to the Margaritiferidae motivated a new search for other potential species of margaritiferids from members of Gibbosula and Lamprotula. Based on molecular and morphological analyses conducted on newly collected specimens from Vietnam, we here assign Gibbosula crassa to the Margaritiferidae. Additionally, we reanalyzed all diagnostic characteristics of the Margaritiferidae and examined museum specimens of Lamprotula and Gibbosula. As a result, two additional species are also moved to the Margaritiferidae, i.e. Gibbosula confragosa and Gibbosula polysticta. We performed a robust five marker phylogeny with all available margaritiferid species and discuss the taxonomy within the family. The present phylogeny reveals the division of Margaritiferidae into four ancient clades with distinct morphological, biogeographical and ecological characteristics that justify the division of the Margaritiferidae into two subfamilies (Gibbosulinae and Margaritiferinae) and four genera (Gibbosula, Cumberlandia, Margaritifera, and Pseudunio). The systematics of the Margaritiferidae family is re-defined as well as their distribution, potential origin and main biogeographic patterns., (Copyright © 2018 Elsevier Inc. All rights reserved.)