Morphological and ecological notes on the swimming crab Achelous hastatus (Linnaeus, 1767) (Family: Portunidae), from Tenerife, Canary Islands (NE Atlantic)

Abstract A voucher-backed adult male specimen of Achelous hastatus (Linnaeus, 1767) was collected on 6 August 2025 during a night dive at 6 m depth off Granadilla, Tenerife, Canary Islands. The specimen was subjected to comprehensive morphometric analysis and documented with high-resolution imagery under controlled laboratory conditions. Morphological features—including a broadly hexagonal carapace with nine anterolateral teeth (ninth markedly elongate), a four-lobed frontal margin, robust chelipeds with slender fingers, and a natatory fifth pereiopod—matched diagnostic descriptions from comparative literature. Field observations documented nocturnal foraging in association with a multi-individual feeding aggregation, scavenging on vertebrate remains. Aggregated occurrence data from the Ocean Biodiversity Information System (OBIS) and the Global Biodiversity Information Facility (GBIF) confirm the species’ widespread Atlantic–Mediterranean distribution, with Spain (including the Canary Islands) representing a primary stronghold. This record contributes high-resolution imagery, morphometric detail, and ecological context to the biogeographic dataset for A. hastatus in the Macaronesian region. Competing Interest Statement The authors have declared no competing interest.