The karyology of Lacerta brandtii (Reptilia, Lacertidae)

The karyotypes of the rare Iranian lacertid Lacerta brandtii and two possib ly related species, Lacerta parva and Lacerta fraasii, were compared. The l atter two species show a diploid number of 24 chromosomes, of which 7 pairs are biarmed, 4 pairs are acrocentric and one microchromosome pair (total n umber of arms, NF=38). They differ only in the morphology of the 7th biarme d pair, which is metacentric in L. parva and subtelocentric in L. fraasii; and in the NOR location found on the telomeres of a large acrocentric pair in L. fraasii and on the microchromosomes in L. parva. Lacerta brandtii dis plays a very different chromosome set, with 2n=38 chromosomes, of which the first pair is subtelocentric, 34 are acrocentric and one pair includes the two microchromosomes (NF=40). The NORs are located on the telomeres of a l arge chromosome pair, a similarity to L. fraasii that we believe is a resul t of convergence. Our data i) support a close systematic relationship betwe en L. fraasii and L, parva; ii) indicate a transition from the L, parva to the L. fraasii karyotype; iii) refute a close taxonomic relationship of L. brandtii with L. parva and L. fraasii; iv) weakly support Arnold's (1989) h ypothesis of a derivation of L, brandtii, Gallotia and Psammodromus from th e same lineage, as all of these taxa possess NF=40.