Primeros estudios cariotípicos en Mimosa farinosa y M. velloziana (Leguminosae, Mimosoideae)

The first karyotype studies in Mimosa farinosaand M. vellozianaare presented. The chromosome number of M. farinosa, 2n = 2x = 26 (Mimosasection Batocaulonseries Farinosae) is mentioned for the first time, while the chromosome number of M. vellozianavar. velloziana, 2n = 4x = 52 (Mimosasection Mimosaseries Mimosasubseries Mimosa) is confirmed. The formula and parameters of karyotype (chromosome length and A1 and A2 asymmetry indexes) were analyzed. The karyotype formula of M. farinosa(16m+10sm) and M. vellozianavar. velloziana (48m+4sm) were calculated. Mimosa farinosahas a more asymmetric karyotype and larger chromosome size than M. vellozianavar. velloziana. A1 index, total chromosome length, and chromosome length per haploid genome showed significant differences between the two taxa. These results agree with differences previously found among other members of series Farinosae and subseries Mimosa, suggesting that certain karyotype parameters could have cytotaxonomic interest in some groups of species of this genus