Allozyme variation in populations of Pleurodema thaul (Lesson, 1826) (Anura; Leptodactylidae).

Genetic variation of 18 loci detected in 13 Chilean and one Argentinian population of the toad Pleurodema thaul are described. Seven loci were polymorphic in at least one of the studied populations. The average heterozygosity values observed for locus went from H = 0.00 for the Las Cardas population to 0.114 in the Lautaro locality, with a global average of 5.2%. The genetic similarity values gave an average of 0.875 (range 0.726-1.00). Accordingly, similarity values were possible to distinguish three groups: north, central and Osorno. The Osorno population differed from the central group in Est-1 and Est-2, yet the Osorno population is only 20 km from a population of the central group.