Chromosomal characterization and comparative cytogenetic analysis of two species of Proechimys (Echimyidae, Rodentia) from the Caatinga domain of the State of Bahia, Brazil

SUMMARY

G-, C-, and R-banding and silver staining techniques were used to analyze the chromosomes of twelve specimens of Proechimys sp. n. (2n = 54; FN = 104) that will be described as a new species by one of us (P.L.B. Rocha) and four of Proechimys albispinus (2n = 60; FN = 116), collected in two localities of the State of Bahia, Brazil. The meiotic studies after silver staining in pachytene cells allowed the visualization of the sex vesicle and the synaptonemal complexes of all autosomal bivalents. Other meiotic phases are studied after conventional staining. A comparative analysis of G-banding patterns among Proechimys sp. n., Proechimys albispinus and Proechimys iheringi iheringi, previously described (YONENAGA-YASSUDA et al. 1985) is presented. These three species are included in the subgenus Trinomys.