Anomalies in Marsh Frogs (Pelophylax ridibundus) and hybrid waterfrogs (P. esculentus) (Anura: Ranidae) from two ponds in the Kharkiv Region of Ukraine

Abstract

Anomalies can be caused by both genetic and environmental factors, with the latter including extreme and unstable conditions such as temperature, pH of water, occupying the margin of the species' range, high density of tadpoles, hormonal imbalances, water pollution, parasitic trematodes, and fungal and other infections (Vershinin 1989; Bezman-Moseyko et al. 2014). Most amphibians are extremely susceptible to environmental conditions because they develop outside of the mother in eggs lacking stiff envelopes (Neustroeva 2012). Vershinin (2015) presented a classification of anomalies based on principal causes: genetic anomalies, ontogenetic anomalies (disruption of development caused by environmental influences), regenerative anomalies (appear in anurans before metamorphosis due to faulty regeneration), and deformities caused by parasites, predators, or injuries.Various amphibian anomalies (e.g., malformed limbs, vertebral column, and head, bone and skin outgrowths, absence or disruption of pigmentation, ocular deformation) have been documented in

Species and hybrid composition and genetic diversity of water frogs (Pelophylax esculentus complex) in western Ukrainian hemiclonal population systems

“…esculentus is most commonly reported in Western and Central Europe, spanning from France to Sweden and Poland, with additional records in Slovakia and Hungary (Holsbeek & Jooris, 2010). In Ukraine, researchers from Kharkiv have identified a specific region in the Siversky Donets River basin as the sole hybridisation centre of water frogs in the country, which is currently the subject of active research (Biriuk et al, 2015;Dedukh et al, 2017;Kryvoltsevych et al, 2022;Stöck et al, 2022).…”