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<p>In the Arctic Ocean, increased sea surface temperature and sea ice retreat have triggered shifts in phytoplankton communities. In Fram Strait, coccolithophorids have been occasionally observed to replace diatoms as the dominating taxon of spring blooms. Deep-sea benthic communities depend strongly on such blooms, but with a change in quality and quantity of primarily produced organic matter (OM) input, this may likely have implications for deep-sea life. We compared the in situ responses of Arctic deep-sea benthos to input of phytodetritus from a diatom (<i>Thalassiosira</i> sp.) and a coccolithophorid (<i>Emiliania huxleyi</i>) species. We traced the fate of ¹³C- and ¹⁵N-labelled phytodetritus into respiration, assimilation by bacteria and infauna in a 4-day and 14-day experiment. Bacteria were key assimilators in the <i>Thalassiosira</i> OM degradation, whereas Foraminifera and other infauna were at least as important as bacteria in the <i>Emiliania</i> OM assimilation. After 14 days, 5 times less carbon and 3.8 times less nitrogen of the <i>Emiliania</i> detritus was recycled compared to <i>Thalassiosira</i> detritus. This implies that the utilization of <i>Emiliania</i> OM may be less efficient than for <i>Thalassiosira </i>OM. Our results indicate that a shift from diatom-dominated input to a coccolithophorid-dominated pulse could entail a delay in OM cycling, which may affect benthopelagic coupling.</p>