Oryzomys alfaroi

alfaroi

Karyotype: 2n = 60 and FN = 104. Autosomal complement: 23 metacentric and submetacentric pairs large to small decreasing in size, and six acrocentric pairs large to small decreasing in size. Sex chromosomes: X, a medium acrocentric; Y, a small acrocentric (Haiduk et al. 1979, pp. 611, Fig. 2B; Baker et al. 1983). G-banding karyotype was performed by Baker et al. (1983). Another karyotype for this species was reported by Musser et al. (1998) 2n = 62 and FN = 100. Autosomal complement: 16 metacentric and submetacentric pairs (four large, four medium, and eight small), four subtelocentric pairs (two large and two medium), and 10 acrocentric pairs (three large, three medium, and four small). Sex chromosomes: X, a large subtelocentric; Y, a small acrocentric.