Esmaeili, H.R., Ebrahimi, M., Teimory, A. and Ansary, T.H. 2008. First karyological analysis of an endemic fish, Isfahan tooth-carp, Aphanius isfahanensis (actinopterygii: cyprinodontidae) from Iran. J. Appl. Anim. Res., 73–76. The karyotype of Isfahan tooth-carp, Aphanius isfahanensis has been investigated by examining metaphase chromosomes spreads obtained from gill epithelial and kidney cells. The diploid chromosome number of this species was 2n=48. The karyotype consisted of 6 pairs of submetacentric and 18 pairs of subtelocentric chromosomes. The arm number (NF) was 30. Sex chromosomes were cytologically indistinguishable in this tooth-carp.