Brachiopod Fauna from the Deep Mediterranean Sea: Distribution Patterns and Ecological Preferences

Compared to their fossil counterparts, living brachiopods are investigated far less often, due occurrence in remote environments such as dark caves or deep environments. Due the scarcity of studies targeting situ brachiopods’ populations, large-scale information on distribution and ecological preferences is still lacking, especially hardgrounds. The extensive employment remotely operated vehicles (ROVs), however, has opened up chance better explore this taxon’s diversity ecology mesophotic bathyal zones. analysis over 600 h video footage collected from 624 sites, 40 m 1825 m, located along Ligurian Tyrrhenian coasts Italy Sicily Channel, allowed for a investigation. four identified species, Novocrania anomala, Gryphus vitreus, Megerlia truncata Terebratulina retusa, emerged common macrofaunal components explored habitats, between 150 250 with high occurrences northern areas, offshore seamounts. All species can form dense aggregations individuals, M. showing densest populations steep rocky terraces (up 773 individuals m−2). Except G. only also recorded soft bottoms, others were found exclusively hardgrounds, N. anomala peculiar ability exploit anthropogenic substrates terracotta amphorae. No stable species-specific associations noted, even if numerous frequently observed together. Although do not show conspicuous tridimensionality large filter-feeders, substrate occupancy role pelagic–benthic processes support importance deep-sea Mediterranean ecosystems.