Karyotypes of Nineteen Marsupial Species From Brazil

Karyotype characterization and nucleolar organizer regions of marsupial species (Didelphidae) from areas of Cerrado and Atlantic Forest in Brazil

“…The Ag-NORs were located at the telomeres of the short arms of pair 6 in M. paulensis ( Figure 2A; Table 1). This result agrees with those reported by Svartman and Vianna-Morgante (2003) and Carvalho et al (2002) for Marmosops incanus and M. parvidens from Goiás and Bahia, Brazil.…”

“…The karyotype of a female Gracilinanus microtarsus from Biritiba-Mirim, São Paulo (Table 1), differed from specimens previously collected in the state of Rio Grande do Sul and also from individuals of G. agilis and G. emilae trapped in Goiás and Minas Gerais (Carvalho et al 2002;this work). While pair 4 was submetacentric and the X chromosomes were metacentric in our specimen of G. microtarsus, pair 4 was metacentric in the specimens of Gracilinanus previously reported and the X chromosome was a submetacentric in G. microtarsus and G. agilis.…”

“…Although marsupial karyotypes have been traditionally considered conservative, the present results indicate that some degree of interspecific karyotype variation occur in Didelphidae. In Gracilinanus, Ag-NORs were located on the short arms of pair 6 in specimens of G. microtarsus and G. emilae, but there are no data for G. agilis (Carvalho et al 2002).…”

“…Some marsupials present a 2n = 14 karyotype, while others exhibit a karyotype with 2n = 22 (Pagnozzi et al, 2000;Svartman and Vianna-Morgante, 2003). The diploid number of 2n = 18 also occurs, but so far it has only been observed in four species of the genus Monodelphis found in Brazil and Bolivia (Pagnozzi et al, 2002;Carvalho et al, 2002).…”

“…Didelphidae belongs to the order Didelphimorphia and is the most diverse American family of marsupials, with 19 genera and 103 species (Wilson and Reeder, 2005). About 25 Brazilian species of marsupials have already had their karyotypes reported (Yonenaga-Yassuda et al, 1982;Casartelli et al, 1986;Souza et al, 1990;Pagnozzi et al, 2000Pagnozzi et al, , 2002Carvalho et al, 2002;Svartman and ViannaMorgante, 1999;Paresque et al, 2004).…”