Abstract:

This paper has dealt with the chromosome numbers and karyotypes of 4 species of the genus tupistra. It is found that all the species studied are diploids with chromosome num-ber 2n=38. The karyotype formula of T.annulata is 2n=2x= 38=34m(2SAT) +4sm,T. fimbriata2n=2x=38=30m+8sm,T.annulata 2n=2x=38=24m (6SAT) + 14sm andT.grandistigma 2n= 2x= 38= 20m+6sm+12st (2SAT) . The karyotypes of T.ensifolia, T. fimbriata, T. annulata are unimodal while the Karyotype of T. grandistigma is bimodal. T.grandistigma is a advanced species in the genus Tupistra.

Key words: Tupistra, Karyotype, Chromosome