Freshwater mollusks of the Valley of Sobaco, Coahuila, Northeastern Mexico – a subfossil ecosystem similar to Cuatrociénegas

Resumen

In the Valley of Sobaco
located in Coahuila, Mexico, were found the remains of an aquatic
ecosystem with a Holocene malacofauna showing similarities to modern
aquatic communities of the internationally famous site of
Cuatrociénegas, located in the state of Coahuila and known as the
"Mexican Galapagos", as it hosts a large number of endemic species.
In addition of ostracods, algae, foraminifera, diatoms and remains
of vascular plants, the Sobaco paleo-pools (pozas) also contain the
gastropods Juturnia coahuilae, Pyrgulopsis manantiali, Coahuilix
hubbsi, Coahuilix cf. landyei and Assiminea cienegensis, which are
endemic species of Cuatrociénegas Valley. Additional discoveries
include sub-recent lacustrine microbial tufas (microbialites,
stromatolites), as well a pool that still contains water hosting
bacterial communities similar to those from Cuatrociénegas. In this
paper we present the taxonomic description of the mollusks from the
Sobaco paleo-lake system and a first reconstruction of the
paleoenvironment. A comparison of this paleoecosystem with modern
aquatic communities of the Cuatrociénegas Valley is also
included.