common otter clam

<em>Lutraria lutraria</em> is a large bivalve mollusc in the family Mactridae, formerly distributed across European marine and coastal habitats, with historical records from Belgium, Denmark, Norway, and Sweden. The species is classified as Extinct by the IUCN, representing one of the documented marine invertebrate extinctions in European waters. It typically inhabits sandy and muddy subtidal and intertidal sediments, burrowing deeply using its elongated siphons, which allow it to feed on suspended particulate matter while buried. The clam is characterized by its broadly oval, gaping shell and prominent external ligament. The extinction of <em>Lutraria lutraria</em> is attributed to habitat destruction, dredging, bottom trawling, and the long-term degradation of coastal sediment environments across its European range. Its loss represents an irreversible reduction in marine benthic biodiversity in the region. Biological traits such as average lifespan, body measurements, and detailed dietary ecology are poorly documented in current standardized databases, particularly given the absence of living populations. The extinction of this species highlights the vulnerability of specialized marine infaunal bivalves to anthropogenic pressures on coastal ecosystems.