(Alstroemeriaceae) is an endemic genus of South America with two major distribution centers in the continent: Chile and Brazil. In Chile the genus is distributed from the North, near Iquique (20° 13' S, 70° 09' W) to the Chilean and Argentine Patagonia (53° 10' S, 70° 54' W). The central zone of Chile presents the highest number of species. A. presliana
Herb. grows from Curicó (34° 59' S, 71° 14' W) to Cautín (38° 45' S, 72° 34' W) in Chile and Neuquén (36° 50' S, 71° 05' W), Argentina. A comparative karyotype study was made between a population of A. presliana
and a population of A. presliana
subsp. australis Ehr. Bayer. Both populations presented asymmetric karyotypes, with 2n
= 16 chromosomes, but with different chromosome formulae: A. presliana
has a haploid formula with 4m + 1sm-sat + 1st-sat + 2t, i.e., four pairs ofmetacentric chromosomes, one submetacentric pair with satellite, one subtelocentric pair with satellite, and two telocentrics pairs. A. presliana
subsp. australis has a formula with 2m + 1m-sat + 1sm + 4t chromosomes, i.e., two pairs of metacentric chromosomes, one metacentric pair with satellite, one submetacentric pair, and four telocentrics chromosomes. These results indicated that the karyotype of the subspecies is very different, and it would be possible to recognize A. presliana
subsp. australis as a new species.