Cytogenetic Studies in North American Minnows (Cyprinidae)

VII. Karyotypes of 13 species from the southern United States

Abstract

We have examined karyotypes of 13 species from eight genera of cyprinid fishes endemic to North America. All thirteen have diploid complements of 50 chromosomes. Arm numbers were estimated for ten species and varied from 46-50 (haploid). The pattern and extent of karyotypic diversity among these 13 species is typical of all North American cyprinids assayed to date. Almost all species have n=25 chromosomes, and variation in arm number is minimal. The conservatism in gross karyotype among these fishes is not commensurate with their apparently rapid and extensive radiation, and suggests that major chromosomal change has played only a minor role in cyprinid evolution.