Data/hora: 09/06/2024 16:31:36

Provedor de dados: 	83	
País: 	Brazil	
Título: 	Karyotype characterization and ZZ/ZW sex chromosome heteromorphism in two species of the catfish genus Ancistrus Kner, 1854 (Siluriformes: Loricariidae) from the Amazon basin	
Autores: 	Oliveira,Renildo R. de; Feldberg,Eliana; Anjos,Maeda B. dos; Zuanon,Jansen.	
Data: 	2007-09-01	
Ano: 	2007	
Palavras-chave: 	Hypostominae; Ancistrini; Cytogenetics; Evolution; Heterochromatin.	
Resumo: 	We present karyotypic characteristics and report on the occurrence of ZZ/ZW sex chromosomes in Ancistrus ranunculus (rio Xingu) and Ancistrus sp. "Piagaçu" (rio Purus), of the Brazilian Amazon. Ancistrus ranunculus has a modal number of 2n=48 chromosomes, a fundamental number (FN) of 82 for both sexes, and the karyotypic formula was 20m+8sm+6st+14a for males and 19m+9sm+6st+14a for females. Ancistrus sp. "Piagaçu" presented 2n=52 chromosomes, FN= 78 for males and FN= 79 for females. The karyotypic formula was 16m+8sm+2st+26a for males and 16m+9sm+2st+25a for females. The high number of acrocentric chromosomes in karyotype of Ancistrus sp. "Piagaçu" differs from the majority of Ancistrini genera studied so far, and may have resulted from pericentric inversions and translocations. The lower number of chromosomes in A. ranunculus indicates that centric fusions also occurred in the evolution of Ancistrus karyotypes. We conclude that karyotypic characteristics and the presence of sex chromosomes can constitute important cytotaxonomic markers to identify cryptic species of Ancistrus. However, sex chromosomes apparently arose independently within the genus and thus do not constitute a reliable character to analyze phylogenetic relations among Ancistrus species.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252007000300010	
Editor: 	Sociedade Brasileira de Ictiologia	
Relação: 	10.1590/S1679-62252007000300010	
Formato: 	text/html	
Fonte: 	Neotropical Ichthyology  v.5 n.3 2007	
Fonte: 	info:eu-repo/semantics/openAccess