O. G. Dely szerk.: Vertebrata Hungarica 21. (Budapest, 1982)
Berger, L., Uzell, Th. ; Hotz, H.: Crossing experiments between some Western Palearctic species of water frogs (Salientia: Ranidae) 33-46. o.
VERTEBRATA HUNGARICA TOM. XXI. 1982 p. 33-45 Crossing experiments between some Western Palearctic species of water frogs (Salientia: Ranidae) By L. BERGER,' Th. UZZELL & H. HOTZ 3 Abstract: Rana perez l from Portugal and southern France and two forms from Sicily (Italian hybrid and non-hybrid) were crossed with R. lessonae. R. rldlbund a and R. e seul ent a from Poland. Crosses of 30 pairs belonged to 12 types. Most of zygotes from all crosses survive through neurula stage. Progeny of nine types of crosses completed metamorphosis and produced vigorous froglets; three crosses involving Italian hybrids had very little success. All progeny of Italian hybrid parents died shortly after completloa embryonal development, and those with R. perez l and R. e seul enta perished as tadpoles or during metamorphosis or shortly thereafter. The Italian hybrid lives and reproductively depends on the Italian non-hybrid, it passes only rldlbund alike genomes to gametes (hybrldogenesis), all progeny fathered by Italian hybrids were females (335:0). Water frogs liye in two disjunct Old World areas: the western and the eastern parts of the Palearctic Region. The western Palearctic water frogs inhabit nearly all of Europe, western and southwestern Asia, and northern Africa. Although many taxa have been named from this large territory (cf. MERTENS & WERMUTH 1960, TERENTJEV 1962), the systematic status of only the three Central European forms (Rana lessona e Camerano, 1882, R. rldlbunda Pallas. 1771, and R. e seul en t a Linnaeus, 1758) has been experimentally established. Based on observations by many authors (cf. BERGER 1977), it Is clear that the first two are Mendelian species, while Rana esculent a is a hemiclonal form (KALLMAN in VRIJENHOEK, ANGUS & SCHULTZ 1977) that arose and arises as a result of hybridization between them. R. esculent a persists in nature by means of hybrldogenetic (SCHULTZ 1969) reproduction (TUNNER 1973, 1974); in its germ line, before the completion of gametogenesis, one of the parental genomes (most often of R. lessonae ) is usually excluded, so that a complete genome of the other parent (most often R. * Paper presented by L. BERGER at the First Herpetological Conference of the Socialist Countries on the 26th August, 1981 in Budapest. 1 Partly supported by the Polish Academy of Sciences within project MR 11/23. 2 Supported by the Smithsonian Institution's Foreign Currency Program and by NSP award DEB 77-13472. 3 Partly supported by the Karl Hescheler-Stiftung, Zürich.
