Adriana Gaytán Caballero ¹ Florence Schubotz ² Ian MacDonald ³ Elva G. Escobar-Briones ^4*

• ¹ Posgrado en Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Mexico City, Mexico, Mexico, Mexico
• ² Organic Geochemistry group, MARUM, Department of Geosciences, University of Bremen, Bremen, Bremen, Germany
• ³ Florida State University, Tallahassee, Florida, United States
• ⁴ National Autonomous University of Mexico, México City, Mexico

The Chapopote Knoll at 3200 m depth, in the southern Gulf of Mexico is highly diverse of asphalt benthic habitats, including surficial gas hydrates with gas seepage. Its associated benthic megafauna includes endemic cold-seep species and background species. This study describes the benthic habitat preferences, distribution patterns and diets of three crustacean species, namely the caridean shrimp Alvinocaris muricola and the galatheids Munidopsis geyeri and M. exuta. High-resolution imaging recorded eight habitats and helped depict the preferences in spatial distribution of the species. A. muricola aggregates on Siboglinidae clusters and in gas seepage sites. M. geyeri and M. exuta, less selective, occurring in almost all habitats. The carbon (δ 13 C) and nitrogen (δ 15 N) values of A. muricola prefer bacteria from mats and water column detritus retained among the Siboglinidae, whereas the two Munidopsis species have wider spectrum diets. Gut content analysis in all three species, validate the stable isotope values, food sources and confirm the secondary consumer's trophic level. This study recognizes coexistence of A. muricola and the two Munidopsis species in the benthic habitats while using different resources. A lipid analysis on galatheids showed depleted values on females (-35‰) and enriched values on males of both species (-28‰) and will require a detailed analysis with a larger sample set to clarify this trophic segregation.