Sampling epifauna, a necessity for a better assessment of benthic ecosystem functioning: An example of the epibenthic aggregated species Ophiothrix fragilis from the Bay of Seine

► Focus on Ophiothrix fragilis as it represents a high biomass in the Bay of Seine and participates in pelago-benthic fluxes. ► Discussion about gear efficiency to sample slow moving epifauna. ► Recommandation on the use of both Smith McIntyre grab and video observation for ophiuroids abundance estimation.