A Cytogenetic Analysis of the Kartortpes of the Golden Shiner, Notemigonus crysoleucase, the Rudd, Scardinus erythrophthalmus, and Their Reciprocal F₁ Hybrids

Abstract

Standard (non-differentially stained) karyotypes of the golden shiner, "Notemigonus crysoleucas", rudd, "Scardinus erythrophtalmus," and their reciprocal F₁ hybrids were documented. Both species possess 2N = 50 chromosomes. The karyotype of the golden shiner is comprised of 7 pairs of metacentric chromosomes, 11 pairs of submetacentric chromosomes, and 7 pairs of subtelo-/telocentric chromosomes, giving a (diploid) chromosome arm number estimate of 86. The karyotype of the rudd is comprised of 6 pairs of metacentric chromosomes, 9 pairs of submetacentric chromosomes, and 10 pairs of subtelo-/telocentric chromosomes, giving a (diploid) chromosome arm number estimate of 80. Reciprocal F₁ hybrids possessed the expected number of chromosomes, i.e., 13 metacentric chromosomes, 20 submetacentric chromosomes, and 17 subtelo-/telocentric chromosomes. Specific marker chromosomes from both species were identified in the F₁ hybrids. These data demonstrate substantial chromosomal differences between the two species, which could lead to chromosomal segregation anomalies in the meiosis of F₁ hybrids; this could result in at least partial sterility.