Redescription of Nanacalathis atlantica Zezina, 1991 (Brachiopoda: Chlidonophoridae) from the North Atlantic

The chlidonophorid brachiopod species Nanacalathis atlantica Zezina, 1991 has been identified in material from the north tropical Mid-Atlantic Ridge, between 16A degrees 56' - 16A degrees 51'N at the depth range 3227-3474 m, collected during the 37th cruise of the RV Professor Logachev in February-March 2015. This rich new material allows us to redescribe and properly illustrate this poorly known, deep-water species that was established on the basis of one empty shell. The spiculation within the lophophore and tentacles is heavy with the pattern characteristic for the subfamily Eucalathinae.