title: AxIOM: Amphipod crustaceans from insular Posidonia oceanica seagrass meadows.
abstract: BACKGROUND
  The Neptune grass, Posidonia oceanica (L.) Delile, 1813, is the most widespread seagrass of the Mediterranean Sea. This foundation species forms large meadows that, through habitat and trophic services, act as biodiversity hotspots. In Neptune grass meadows, amphipod crustaceans are one of the dominant groups of vagile invertebrates, forming an abundant and diverse taxocenosis. They are key ecological components of the complex, pivotal, yet critically endangered Neptune grass ecosystems. Nevertheless, comprehensive qualitative and quantitative data about amphipod fauna found in Mediterranean Neptune grass meadows remain scarce, especially in insular locations.
  
  
  CONCLUSIONS
  Here, we provide in-depth metadata about AxIOM, a sample-based dataset published on the GBIF portal. AxIOM is based on an extensive and spatially hierarchized sampling design with multiple years, seasons, day periods, and methods. Samples were taken along the coasts of Calvi Bay (Corsica, France) and of the Tavolara-Punta Coda Cavallo Marine Protected Area (Sardinia, Italy). In total, AxIOM contains 187 samples documenting occurrence (1775 records) and abundance (10720 specimens) of amphipod crustaceans belonging to 72 species spanning 29 families. The dataset is available at http://ipt.biodiversity.be/resource?r=axiom.
authors.affiliation: Laboratory of Oceanology, FOCUS research unit, University of Liege, Liege, Belgium.
authors.forename: Loïc N
authors.initials: LN
authors.lastname: Michel
authors.affiliation: Laboratory of Oceanology, FOCUS research unit, University of Liege, Liege, Belgium.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Sturaro
authors.affiliation: Belgian Biodiversity Platform, Bruxelles, Belgium.
authors.forename: André
authors.initials: A
authors.lastname: Heughebaert
authors.affiliation: Laboratory of Oceanology, FOCUS research unit, University of Liege, Liege, Belgium.
authors.forename: Gilles
authors.initials: G
authors.lastname: Lepoint
keywords: Amphipoda; Corsica; Crustacea; Hierarchical sampling design; Islands; Mediterranean; Posidonia oceanica; Revellata Bay; Sardinia; Seagrass; Tavolara - Punta Coda Cavallo Marine Protected Area