Genetics and Molecular Biology (Jan 2008)

Cytotaxonomy and karyoevolution of the genus Crenicichla (Perciformes, Cichlidae)

  • Denise Corrêa Benzaquem,
  • Eliana Feldberg,
  • Jorge Ivan Rebelo Porto,
  • Maria Claudia Gross,
  • Jansen Alfredo Sampaio Zuanon

DOI
https://doi.org/10.1590/s1415-47572008000200016
Journal volume & issue
Vol. 31, no. 1
pp. 250 – 255

Abstract

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Karyotypes of six cichlid species of the genus Crenicichla were investigated. The species C. cincta, C. inpa, C. reticulata, C. lugubris, and C. cf. johanna were collected from Amazon basin, and C. britskii was collected from the Paraná-Paraguai basin. All of the analysed species showed 2n = 48 chromosomes; however, C. cincta, C. lugubris, C. cf. johanna, and C. britskii had a karyotype formula of 8M-SM+40ST-A, FN = 56, while C. inpa and C. reticulata exhibited the formula 6M-SM+42ST-A, FN = 54. Analysis of active Ag-NORs revealed two NOR-bearing chromosomes in all species; however, theses cistrons were located on different chromosome pairs and/or in different chromosome locations in each species. This condition bears evolutionary significance, since it is the main chromosome marker of the process of karyotypic evolution among the species of the genus Crenicichla. In general, C-banding revealed a similar constitutive heterochromatin pattern in all species, although it was possible to detect some features that led us to infer that Crenicichla also presents a species-specific heterochromatin pattern.

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