Title:	Citotaxonomia de acestrorhynchus (characiformes) da região amazônica / Alber Sousa Campos
Authors:	Campos, Alber Sousa
metadata.dc.contributor.advisor:	Feldberg, Eliana
Keywords:	Rearranjos cromosômicos DNAr 28 DNAr 5s espécies cripíticas
Issue Date:	29-Jun-2019
Publisher:	Instituto Nacional de Pesquisa da Amazônia - INPA
metadata.dc.publisher.program:	Genética, Conservação e Biologia Evolutiva - GCBEv
metadata.dc.description.resumo:	Acestrorhynchinae is a subfamily of Acestrorhynchidae (Characiformes) that has only a genus, Acestrorhynchus, with 14 valid species. Since it was established as a monophyletic group and recognized in family level, this group is undergoing reviews regarding taxonomic relationship with other fish families. Moreover, there are also taxonomic problems in the genus, which one is divided into three groups according to color pattern: lacustris group, nasutus group and microlepis group. The similarity among the species in juvenile phase and the differences among individuals of the same species have been the goal of researches to establish this relationship. In this work it was analyzed four species of this subfamily: Acestrorhynchus falcirostris, A. falcatus, A. microlepis and A. cf. microlepis, collected in three localities in Amazon, with the goal to identify species-specifics chromosomic characteristics that could serve as base to understand these relationships. For this, it was used classic cytogenetic techniques (Giemsa, Ag-NOR, C-banding) and molecular cytogenetic (fluorescence in situ hybridization - FISH). With regard karyotypic structure, all the species showed diploid number equal to 50 chromosomes with two arms, and fundamental number (FN) equal 100, but with differences in the karyotypic formula. The heterochromatic pattern was species-specific, with C-positive bands in the centromeric and bitelomeric regions of several chromosomes, besides some interstitial blocks and totally heterochromatic arms. The nucleolus organizing region (NOR) was simple, terminal in short arm (pair 23), coincident with a secondary constriction in three species, except A. microlepis that showed it in the long arm. However, the mapping of 18S rDNA was multiple in two species (A. falcatus and A. microlepis). The 5S rDNA was localized in a chromosomic pair in all the species. The telomeric probe highlighted terminal regions in all chromosomes, as well as the presence of interstitial sequences (ITS) in several chromosomic pairs. The obtained results in this study makes clear the importance of chromosomic markers to establish a comparative way among fish groups but mainly to confirmation of cryptic species as discovered in A. microplepis.
Appears in Collections:	Mestrado - GCBEv

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