Background.

The Sontecomapan Lagoon is a protected natural area and is part of the Los Tuxtlas Biosphere Reserve on the south coast of the State of Veracruz, with significant fishing productivity and little ecological knowledge about its fish community.

Objectives.

Analyze space-time variations in diversity, richness, abundance, dominant species, community inhabitants, fish assemblages, and trophic groups.

Methods.

The fish collections were made between 2014 and 2020, in 10 stations with a trawl net. The sampling effort was validated using non-parametric estimators. Analysis of variance was used to indicate statistically significant differences in community ecological parameters between sites and months. Canonical correspondence analysis (ACC) was performed to determine species-habitat relationships.

Results.

Fifty species, 35 genera and 23 families were identified, with 2 new records, Chaetodipterus faber (Broussonet, 1782) and Pomadasys ramosus (Poey, 1860) and 2 dominant species, Diapterus rhombeus (Cuvier, 1829) and Cathorops aguadulce (Meek, 1904). The diversity values ​​(H´ = 0.84 to 2.07, D = 2.36 to 3.83, J´= 0.26 to 0.64) and abundance (density = 0.009 to 0.035 ind./m2, biomass = 0.105 to 0.044 g/m2, average weight = 5.91 to 16.72 g/ind), are considered low compared to other similar coastal systems. The spatial and temporal fluctuations of these parameters are related to the life cycles of the species present and with the environmental dynamics of the system. The ACC analysis indicated that fish assemblages are determined by changes in salinity, transparency, and depth.

Conclusion.

The ecological information analyzed represents a broad frame of reference for a little-studied coastal area that requires management and conservation strategies for its biotic resources.