Macrofauna abundance and diversity patterns of deep sea southwestern Gulf of Mexico

The diversity and distribution of macrofaunal communities in the deep-sea bottoms Gulf Mexico (GoM) Mexican waters are poorly known compared to northern GoM. This study was designed contribute knowledge macrofauna through (i) evaluate taxonomic composition at major taxa level, (ii) analyze spatial patterns deep sea southwestern Benthic analyzed a large geographical area (92.67°–96.70° W 18.74°–23.04° N) bathymetric gradient (185-3740 m depth). Samples were collected on board R/V Justo Sierra (Universidad Nacional Autónoma de México) with Reineck-type box corer during oceanographic cruises SOGOM-3 SOGOM-4 carried out April 21–May 15, 2017, August 29–September 20, 2018, respectively. Thirteen environmental parameters measured (among them, depth, salinity, temperature, O2, sediment grain size, hydrocarbons, organic matter). Twenty-five registered SOGOM 3 (2315 individuals) all which observed 4 (1721 exception mollusk Class Solenogastres. average abundance (ind. -2 ) 517 (range: 150-1388 ind. ), 347 38-1088 for 3, 4, In Polychaeta, Nematoda, Amphipoda, Tanaidacea, Bivalvia contributed 75% total abundance, also most abundant representing 82% abundance. Highest south near coast, lowest one found deeper areas. Macrofauna decreased depth both cruises. High values intermediate depths west zones area. Both separated nMDS analysis. During dissolved oxygen, aromatic matter (%) variables related whereas, important one. fills gap covering whole range southern provides baseline useful compare polluted areas assessing impact chronic pollution and/or potential oil spill accidents.