Springtails (Collembola, Hexapoda) from Montebello Lakes, Chiapas, Mexico

ABSTRACT

Springtails are mostly terrestrial organisms, relatively rare in truly aquatic environments; a few are neustonic while others are found in humid caves, surfaces, and crevices of marine coastal zones. We have found them in the benthic zone of 4 deep lakes, Bosque Azul, Dos Lagos, Ensueño, and Tziscao of Lagunas de Montebello National Park in Chiapas. We recovered 43 specimens belonging to 13 species from the samples, all of which except Americabrya arida were first records for the state of Chiapas; the most abundant were A. arida and Lepidocyrtus lanuginosus. Species richness of each lake varied between 1 and 12; density varied between 15 ± 25 and 133 ± 118 org m⁻², and biomass varied between 0.02 and 4.3 ± 4.4 and 0.02 μg m⁻². Tziscao showed the highest abundance (35 individuals), species richness (12 species), and density (133 ± 118 org m⁻²), and Bosque Azul showed the highest average biomass (4.3 ± 4.4 μg). Together, 96% of the organisms were collected during summer when lakes were thermally stratified (warm monomixis); 44% of the organisms were recovered from deep anoxic samples (>20 m). Springtails were found living in warm waters in conditions varying from well oxygenated to anoxic, a slightly basic pH range (7.1–8.3), and a high range of electric conductivity (219.7–1716.0 μS cm⁻¹) values. Sediments were mainly composed of sands and mud (silt and clay) with a wide organic matter range (15.4–51.2%) and sedimentary carbonates (6.0–98.3%). Of the 43 specimens, 17 were adults (12 males and 5 females) and 26 were immature, both with gut content composed mostly of Cladosporium hyphae and conidia. These are the first records of submerged Collembola inhabiting the deep benthic zones of Mexican lakes.

KEYWORDS:

• aquatic springtails
• biomass
• density
• habitat
• species richness

Acknowledgements

This research was granted by the Fondo Sectorial de Investigación y Desarrollo Sobre el Agua (Sectorial Fund for Water Research and Development) (CONAGUA-CONACYT) through the project “Estudio hidrológico y de Calidad del Agua del sistema Lagunar de Montebello, en el estado de Chiapas” and by Dirección General de Asuntos del Personal Académico (PAPIIT-IN219215) through the project “Factores que determinan el estado trófico de los lagos de Montebello, Chiapas.” We thank René Morales Hernández and Luis Oseguera and collaborators for support during the fieldwork. We also thank the Parque Nacional Lagunas de Montebello, Comisión Nacional de Áreas Naturales Protegidas (CONANP) (Jesús A. León and Roberto Castellanos), the local community, and the Comisariados Ejidales from Antelá, Cárdenas, Miguel Hidalgo, Ojo de Agua, and Tziscao for facilitating access to the lakes. We also thank the Comité de Administración de Tziscao (Sergio Marcos and Miguel A. Tomas), Presidente del Comité de Turismo de Tziscao (Armando Hernández), Comisario Ejidal de Tziscao (Enrique M. Hernández), and personnel of the Villas Tziscao Hotel (Rosemberg F. Jorge, Juan G. Espinoza and Gemuel P. Hernández) for offering their support and facilities for this study. Dra. Blanca Mejía Recamier prepared the slides for identifying the springtails. M. C. Carmen Nuñez, Universidad Veracruzana, identified the fungi found in the gut content. Jesús Cruz Leal verified the databases of Mexican aquatic Collembola and particularly those from Chiapas (Proyecto LE002 CONABIO), Facultad de Ciencias, UNAM. An anonymous reviewer provided thoughtful comments for improving the manuscript.