Integrative taxonomy reveals a new species, Anadara adiastola sp. nov. (Bivalvia, Arcidae) from the northern Arabian/Persian Gulf, north-western Indian Ocean

A new species of the arcid genus Anadara is described from intertidal and shallow subtidal habitats in Kuwait, northern Arabian/Persian Gulf. Anadara adiastola sp. nov . is diagnosed using shell morphology and soft-part anatomy and further assessed through COI sequence data. The new species is characterised by an oblong to subtrapezoidal shell, 31–35 radial ribs, weak cross bars mainly on the anterior ribs, and a thick periostracum forming long bristles, especially on the posterior slope. This combination of characters distinguishes it from all Anadara species previously recorded from the Arabian/Persian Gulf, Arabian Sea, and western Indian Ocean. COI sequences from Kuwaiti specimens formed a distinct and highly divergent lineage within Anadarinae, clearly separated from all available GenBank lineages and from the regional taxa considered morphologically. The nearest molecular lineages in public databases are geographically distant and include records affected by probable misidentifications, highlighting the current limitations of GenBank for comparative taxonomy in Anadara while supporting the distinctiveness of the Kuwaiti lineage. The integrative taxonomic approach combining morphological, anatomical, geographic, and molecular evidence supports the recognition of A. adiastola sp. nov . as a distinct species.