Studied localities (n = 68) in the Middle Volga River drainage, where live three Pelophylax species (black dots; Svinin et al. 2021), and 8 localities with the anomaly P syndrome (red spots). A, B. Severe forms of the anomaly P in the pool frog (P. lessonae) from Gusevo village (Mari El Republic, Russia). Borders of Mari El Republic are designated by gray line and forests by light green fill.

  Part of: Svinin AO, Ermakov OA, Litvinchuk SN (2022) The incidence of the anomaly P syndrome in water frogs (Anura, Ranidae, Pelophylax) from the Middle Volga River (Russia). Herpetozoa 35: 283-288.