Aguanaval: Rio Florido at Atotonilco

Conservación: For the first time in this other times pristine location, during my last visit (Artigas Azas, 2023) I found the river quite polluted from sewage, likely from the nearby town of Miguel Hidalgo, above the regular sand substrate, a thick layer of black mud was present, as well as an abundance of green algae. This may be the reason why on this occasion we could not find a single Etheostoma pottsi at the place, which was very common in any of the many previous visits I have made to this place. It seems however that up the river or in another nearby branch the situation may be different. It remains to be seen.