Squalius laietanus, a new species of cyprinid fish from north-eastern Spain and southern France (Teleostei: Cyprinidae)

Squalius laietanus, new species, is described based on morphological and genetic characters. It occurs from the Ebro to Port Bou drainages in Spain and in the Tech and Agly drainages in France. It differs from the other species of Squalius in western Europe by a combination of: a slightly subinferior mouth, with a slightly projecting tipper lip and the tip of the lower jaw enclosed in the upper lip; flank scales margined by a band of black pigments along their free margin, forming a regular reticulate pattern; brown pigments on the inner area of the scales, more densely set on the upper and lower extremity of the exposed part, the pigment patches often appearing as faint longitudinal stripes between scale rows; and no or little marked discontinuity between the dorsal profile of head and body. Based on molecular characters, S. laietanus is most closely related to S. orpheus from Thrace (Greece and Turkey).