Occurrence of B chromosomes in Tetragonisca Latreille, 1811 (Hymenoptera, Apidae, Meliponini): a new contribution to the cytotaxonomy of the genus

• Autor(a) principal: Barth,Adriane
• Data de Publicação: 2011
• Outros Autores: Fernandes,Anderson, Pompolo,Silvia das Graças, Costa,Marco Antônio
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Genetics and Molecular Biology
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000100014
• topic: stingless bees; cytogenetics; interspecific differentiation; B chromosomes

Tetragonisca angustula and Tetragonisca fiebrigi have recently been listed as valid species. This study aimed to cytogenetically investigate both species, emphasizing the new registry of B chromosomes in the tribe Meliponini. We analyzed colonies of T. angustula and T. fiebrigi collected at Tangará da Serra, Mato Grosso, Brazil, through conventional Giemsa staining, C-banding, and base-specific fluorochrome staining (CMA3/DAPI). T. angustula showed 2n = 34 chromosomes in females and n = 17 in males, with karyotype formula 2K = 34A M. T. fiebrigi showed numeric variation, with chromosome number varying from 2n = 34 to 2n = 36 in females and from n = 17 to n=18in males, with karyotype formula 2K = 32A M+2A Mc and 2K = 32A M+2A Mc + 1 or 2 B-chromosomes. The B chromosomes are heterochromatic. In T. fiebrigi, the CMA3/DAPI staining revealed four chromosomes with a CMA3 positive band. All individuals from the same colony showed the same number of B chromosomes. T. angustula and T. fiebrigi showed karyotype divergence, principally due to the presence of B chromosomes, which are found only in T. fiebrigi. Our data corroborate the status of valid species for both T. angustula and T. fiebrigi, as recently proposed.