Subterranean Fishes of the World

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2026

Subterranean Biology

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Copyright Brenda Durán & Fernando Álvarez This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the origin

With the aim of describing the isotopic niche of the anchialine shrimps of the genus Typhlatya from the Yucatan Peninsula (YP) we analyze a dataset that includes three of the four species present in the region using published and new δ13C and δ15N values. Typhlatya shrimps are recognized as ecologically important in the anchialine food web due to their ample distribution, relatively high abundance and feeding characteristics. The variation in δ13C values shows that Typhlatya shrimps cover almost the complete interval of the whole anchialine community reflecting the different nutrient sources they can feed on; the three species separately have δ13C ranges that partially overlap, becoming more negative starting with T. mitchelli, followed by T. dzilamensis and T. pearsei. The δ13C ranges for T. mitchelli and T. pearsei from four cenotes did not change between the rainy and dry seasons. By region, the δ13C ranges for the whole anchialine community in the Ring of Cenotes are narrower and less negative than those from the Caribbean Cave Area, reflecting the different geomorphology and hydrology of the two regions. The isotopic niches of T. mitchelli and T. pearsei, the two dominant species in the freshwater lens, overlap around 20% leaving an ample margin for coexistence. Typhlatya pearsei has the most negative δ13C values which are consistent with feeding on microbial biomass, including methanotrophic bacteria. The isotopic niches of the three Typhlatya species studied although somewhat variable, are well defined and compose a well structured community. Keywords Anchialine, atyid shrimps, δ13C, δ15N, Isotopic niche, Yucatan Peninsula

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