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Chromosomal painting and ZW sex chromosomes differentiation in Characidium (Characiformes, Crenuchidae)
(Biomed Central Ltd., 2011-07-25)
Background: The Characidium (a Neotropical fish group) have a conserved diploid number (2n = 50), but show remarkable differences among species and populations in relation to sex chromosome systems and location of nucleolus ...
A new karyotype of oligoryzomys (sigmodontinae, rodentia) from central Brazil
(2003-09-01)
A new karyotype of the genus Oligoryzomys was described for specimens collected in Brazilian Cerrado in Tocantins and Goias States. Conventional staining, G-, C-banding, and Ag-NOR staining techniques were used for describe ...
Karyotype characterization, constitutive heterochromatin and nucleolus organizer regions of Paranaita opima (Coleoptera, Chrysomelidae, Alticinae)
(Sociedade Brasileira de Genética, 2006-01-01)
Species of the subtribe Oedionychina not only have a highly uniform diploid number of 2n = 22 (20+X+y) but have the karyotypic peculiarity of possessing extremely large sex chromosomes. We analyzed Paranaita opima embryos ...
Evidence of an XX/XY sex chromosome system in the fish Dormitator maculatus (Teleostei, Eleotrididae)
(Sociedade Brasileira de Genética, 2006-01-01)
The fish Dormitator maculatus has a chromosomes number of 2n = 46, females having a karyotype of 14 M, 28 SM, 2 ST and 2A and males 13 M, 28 SM, 3 ST and 2A. The presence of a heteromorphic pair in the males and a corresponding ...
Chromosome studies of Brazilian vespertilionids Lasiurus cinereus and Lasiurus ega (Mammalia, Chiroptera)
(Museu de Ciências Naturais, 2004-12)
Cytogenetical studies based on conventional coloration by Giemsa, C-banding and Ag-NOR were performed on 2 species of bats from the vespertilionid family: Lasiurus cinereus (Beauvois, 1796) and Lasiurus ega (Gervais, 1856). ...
Chromosomal differentiation of Hyla nana and Hyla sanborni (Anura, Hylidae) with a description of NOR polymorphism in H-nana
(Oxford University Press, 2003-03-01)
Specimens of Hyla nana and Hyla sanborni from a syntopic population were studied cytogenetically. These species are morphologically very similar and are frequently misidentified, confused with each other. Both species had ...
Chromosome Studies in Hypoptopomatinae (Pisces, Siluriformes, Loricariidae): L. XX/XY Sex Chromosome Heteromorphism in Pseudotocinclus tietensis
(1992-01-01)
The cytogenetic analysis of 13 specimens (9 males and 4 females) of Pseudotocinclus tietensis showed that this species has 2n=54 chromosomes (26M+20SM+6ST) plus one heteromorphic pair (SM/M) in the males and one homomorphic ...
A natural triploid in Trichomycterus davisi (Siluriformes, Trichomycteridae): mitotic and meiotic characterization by chromosome banding and synaptonemal complex analyses
(Kluwer Academic Publ, 2002-08-01)
Within a total of 50 analyzed specimens a male individual of Trichomycterus davisi has been recorded with 81 chromosomes including 60 metacentric, 18 submetacentric and three subtelocentric chromosomes. When compared with ...
KARYOTYPE and NUCLEOLUS ORGANIZER REGIONS of Ophisternon aenigmaticum (Teleostei: Synbranchiformes: Synbranchidae) FROM VENEZUELA
(Interciencia, 2011-03-01)
The first cytogenetic analysis by conventional Giemsa staining silver nitrate impregnation of nucleolus organizer regions (Ag-NOR), and fluorescence in situ hybridization (FISH) carried out on Ophisternon aenigmaticum from ...
Chromosomal characteristics and karyotype evolution of oxyopidae spiders (araneae, entelegynae)
(2011-05-16)
We made a cytogenetic analysis of four species of Oxyopidae and compared it with the karyotype data of all species of this family. In Hamataliwa sp, the mitotic cells showed 2n♂ = 26+X 1X 2 and telocentric chromosomes. The ...