The meiofauna of the Eratosthenes Seamount (eastern Mediterranean Sea)—first insights into taxa composition, distribution, and diversity

Abstract

During the research cruise MSM 14/1 of RV M.S. MERIAN to the eastern Mediterranean Eratosthenes Seamount in 2009/2010, samples were taken with a multiple corer to get first insights into the composition, abundance, and diversity of the meiofauna. Along two transects, a north–south and a west–east ones, 14 sites were sampled on the seamount. Additionally, a distant deep-sea site provided meiobenthic material for comparison with that of the seamount. Altogether, 15 meiobenthic major taxa were found. Nematoda and Copepoda Harpacticoida strongly dominated all sites, followed by Annelida and Tardigrada at most sites. Although direct comparison pointed towards a northern seamount community, this could not be confirmed by a detailed community analysis regarding taxa composition, abundance expressed by density (ind./10 cm2), and taxa diversity. It revealed neither a homogeneous seamount community nor any faunistic relation with bathymetric or geographic gradients, with exception of the taxa diversity that apparently followed a latitudinal gradient. Generally, Eratosthenes Seamount presents a quite heterogeneous meiobenthic assemblage that may be linked to small-scale biotic and abiotic variables. Moreover, also the distant reference site did not differ significantly from the seamount sites. A brief comparison with other Atlantic and Mediterranean seamounts and islands indicates that Eratosthenes Seamount is not characterized by an impoverished meiobenthic fauna.