Seminemacheilus is a genus of small stone loaches in the family Nemacheilidae, restricted entirely to Turkey. The atlas covers 7 species, ranging from about 2–3.5 in, all drawn from Anatolian spring-fed streams, karst-fed watercourses, and other cool, well-oxygenated freshwater habitats typical of the region's interior plateau. Like other nemacheilid loaches, they have an elongate, scaleless or near-scaleless body, a flattened underside, and barbels around a small downturned mouth adapted to picking invertebrates and detritus off gravel and stone substrate.
Two species carry English names in the atlas — the Southern pond loach (Seminemacheilus ispartensis) and the Anatolian loach (S. lendlii) — but the genus as a whole is essentially unknown in the aquarium trade and is of almost purely scientific and conservation interest. Many Seminemacheilus species are confined to single spring systems or short stretches of stream, a pattern of narrow endemism that shows up starkly in the conservation tally: alongside four species not yet formally assessed, the atlas records a Critically Endangered species along with an Endangered and a Vulnerable one, consistent with small-range freshwater fish vulnerable to groundwater extraction, spring capture, and habitat modification across Anatolia.