LAUSR

Benthic macroinvertebrate community biodiversity of tropical lakes has been rarely addressed. The present study recognizes the taxonomic diversity of the deep benthic macroinvertebrate communities of 18 lakes of the Protected Natural Area "Lagunas de Montebello", Chiapas, Mexico. The lakes display different morphometric features and trophic states. Five sampling campaigns were carried out between 2013 and 2016. Forty-nine taxa (14 orders, 25 families, 40 identified genera, and 9 undetermined taxa) were recorded. Taxonomic richness varied between 0 and 19 taxa with a mean of 5 ± 6 taxa. The regional species richness was high compared to other tropical lakes in Mexico and worldwide; the richness per lake was similar to other tropical lakes. Chironomidae was the best-represented family with 17 genera. Even the studied lakes belong to the same lake district, low taxonomic similarity among them was found; 65.3% of genera were found in a single lake. Eutrophic shallow lakes had lower richness (2.5 ± 3.5, 0-5) compared to oligotrophic shallow lakes (5.0 ± 7.1, 0-10), and eutrophic deep lakes had lower richness (2.0 ± 1.8, 0-4) than oligotrophic deep lakes (7.0 ± 6.5, 0-19); nonetheless, we found no statistically significant differences. Eutrophication is reducing deep benthic community diversity, threatening these fragile ecosystems characterized by high taxonomic richness and singularity.