Resumo

RAMIREZ-NAVA, Maripili; CABALLERO, Margarita  e  VAZQUEZ, Mercedes. Iconella guatimalensis (Ehrenberg) Ruck & Nakov (Bacillariophyta) as an indicator species for low lake level conditions in three lake sedimentary records from central Mexico. TIP [online]. 2021, vol.24, e384.  Epub 17-Abr-2023. ISSN 1405-888X.  https://doi.org/10.22201/fesz.23958723e.2021.384.

Iconella guatimalensis is a large freshwater diatom, initially described in material from Guatemala and reported in various locations in the Neotropics. However, it has only been confirmed in two locations for modern environments in Mexico. In this paper we report the presence of this species in low abundances (<10%) in the Holocene sedimentary records of lakes Santa María del Oro (SMO) and Coatetelco (COA). A morphological description was integrated from observations of several specimens in light and scanning electron microscopy. The distribution of this species in the two lakes coincides with time windows that have been identified as shallow-water environments and dry climates (Late Classic Drought A.D. 600-1000 and the Little Ice Age, A.D. 1315-1860). The distribution of I. guatimalensis also agrees with increases in the abundances of other benthic diatoms in SMO, corroborating that it can be considered as an indicator of periods with low lake levels. The times of maximum abundances of this species in the two combined records were: B.C. 3100-2300 (5050-4260 B.P.); B.C. 1040-580 (3000-2530 B.P.); A.D. 50-900 (1900-1050 B.P.); y A.D. 1315-1860 (635-90 B.P.).

Palavras-chave : continental diatoms; Surirellales; paleoindicator; paleolimnological record; lake.

        · resumo em Espanhol     · texto em Espanhol     · Espanhol ( pdf )