Gravel chub silt and debris. They are more often found in areas with limited macrophytes and larger root aquatic plants, algae and moss. Because of their need of a specialized clean habitats, the gravel chub is especially vulnerable to various forms of pollution, especially from agriculture practices that create erosion and excessive silt. In past sampling surveys the gravel chub had been found as far north in the Upper Iowa River as Le Roy, Minnesota, but because of excessive amounts of sewage, pesticides and sedimentation of rocks and sand, this is no longer the case. The presence of gravel chubs in a
Granular pugolovka Granular pugolovka The granular pugolovka ("Benthophilus granulosus") is a species of gobiid fish widespread in the Caspian Sea. It is a small fish, with a length up to TL. It was listed as Least Concern by the IUCN in 2008: there are no known major threats. Granular pugolovkas are very abundant in their habitat due to their size and lack of natural predators. The common name 'pugolovka' is a Ukrainian word for tadpole. "Benthophilus granulosus" has a flat head with a flat barbel on the chin that is often described as being leathery. The body colors depend on the habitat