There are three taxons of central European water frogs of the Pelophylaxesculentus complex: two morphologically distinct species, Pelophylaxlessonae (LL) and Pelophylaxridibundus (RR), and hybrids Pelophylaxesculentus, which can be either diploid (RL) or triploid (LLR or RRL). The morphology of hybrids is supposed to follow genome dosage effect. We describe colouration of water frogs with genome composition verified by chromosome analysis. Typical colouration features in LL were: spots on the ventral side, brown limbs, “weak” femur spotting pattern, brown dorsal folds and yellow-green colour in “waist”. Typical RR had dark-green or olive-green limbs, “full” femur spotting pattern, no hip spot and no yellow colour in “waist”. For all hybrids the most typical features were strong spots on the ventral side and a mosaic of green and brown colour on limbs. Typical LLR had brown-greenish dorsal folds underlined by a partial black line, “weak” femur spotting pattern and yellow-greenish colour in “waist” and on femur. Typical RL had greenish hind limbs, green dorsal folds, no yellow colour in “waist”, and no hip spot. Typical RRL was similar to RL, but had a continuous black line under dorsal folds. There were, however, numerous exceptions to these trends, with the most prominent being much higher than expected variability of colouration of Pelophylax lessonae. Therefore caution must be advised when trying to estimate genome composition of water frogs solely on the basis of colouration.
Coexistence of diploid and triploid hybrid water frogs: population differences persist in the apparent absence of differential survival.
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Genome dosage effect and hybrid morphology — the case of the hybridogenetic water frogs of the Pelophylax esculentus complex.
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DNA content and genome composition of diploid and triploid water frogs belonging to the Rana esculenta complex (Amphibia, Anura).
Canadian Journal of Zoology82:
Morphometric and DNA investigations into European water frogs (Rana kl. esculenta Synklepton (Anura, Ranidae)) from different population systems.
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Proceedings of The Academy of Natural Sciences of Philadelphia127 (2):
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Proceedings of The Academy of Natural Sciences of Philadelphia27 (11):
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Proceedings of the Academy of Natural Sciences of Philadelphia128 (9):
Evidence for integrity of parental genomes in the diploid hybridogenetic water frog Pelophylaxesculentus by genomic in situ hybridization.
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