Chromosomes of Gymnothorax funebris and the karyotypical differentiation within Gymnothorax (Anguilliformes: Muraenidae)

Abstract

ABSTRACT. Cytogenetic studies in Gymnothorax funebris revealed a diploid chromosome number 2n = 42 (6 metacentrics, 4 submetacentrics, and 32 acrocentrics, FN = 52). The results obtained are novel and similar to those previously described for species belonging to Muraenidae family. The conventional karyotype is also novel and divergent from other species of the genus Gymnothorax, where a higher proportion of metacentric chromosomes predominate. The data are reported and discussed considering the cytotaxonomy of the genus. These results strongly support the current view that chromosomal alterations such as centric fusion and Robertsonian's translocations have an important role in the evolution of this group.

Comparative cytogenetics of six Indo‐Pacific moray eels (Anguilliformes: Muraenidae) by chromosomal banding and fluorescence in situ hybridization

“…For most species in this study, a large amount of constitutive heterochromatin was detected with species‐specific C‐banding patterns that enabled pairing of the homologous chromosomes. The presence of large heterochromatic blocks, mainly localized in the pericentromeric and telomeric positions, appears to be a common feature in the Muraenidae (Cau et al , ; Salvadori et al , , ; Porto‐Foresti et al , ; Vasconcelos & Molina, ; Alves et al , ). The variations in quantity, position and properties of the heterochromatin suggest that the constitutive heterochromatin could play an important role in the karyotype evolution of the Muraenidae, as previously demonstrated for the Cyprinidae (Ueda et al , ).…”

“…cytogenetics) can potentially provide important information to address the aforementioned uncertainties in the systematics, taxonomy and phylogeny of muraenids. To date, the karyotype structure is known for only 14 species of muraenid, and for most of these only C‐banding patterns and silver‐stained nucleolar organizer regions (Ag‐NOR) phenotypes are available (Coluccia et al , ; Arai, ; Alves et al , ). Representative muraenids show a conserved diploid chromosome number (2n = 42); nevertheless, chromosomal rearrangements have been observed in several species resulting in divergent karyotype structures (Salvadori et al , ; Vasconcelos & Molina, ; Coluccia et al , ).…”