Artículos de revistas
Genetic differentiation among distinct karyomorphs of the wolf fish Hoplias malabaricus species complex (Characiformes, Erythrinidae) and report of unusual hybridization with natural triploidy
Fecha
2014-11-01Registro en:
Journal Of Fish Biology. Hoboken: Wiley-blackwell, v. 85, n. 5, p. 1682-1692, 2014.
0022-1112
10.1111/jfb.12526
WOS:000343970400023
0804793944846367
Autor
Universidade Estadual Paulista (Unesp)
Univ Ensino Super Inga
Universidade Federal de São Carlos (UFSCar)
Institución
Resumen
In this study, genetic differentiation between karyomorphs A (2n=42) and D (2n=39/40) of the wolf fish Hoplias malabaricus, which is comprised of several cryptic species that present a wide variety of diploid chromosome numbers and sex chromosome systems, resulting in the identification of seven distinct karyomorphs (A-G), was investigated using a combination of molecular and cytogenetic tools. Deep sequence divergences for both karyomorphs were observed and indicate a long period of reproductive isolation between karyomorphs A and D. Additionally, one individual with 61 chromosomes was identified, which, as far as is known, is the first case of natural triploidy resulting from the hybridization between these highly differentiated karyomorphs of H. malabaricus. Molecular and cytogenetic analyses revealed that this allotriploid specimen carries two sets of maternal chromosomes from karyomorph D (2n=40) and one set of chromosomes from karyomorph A (n=21). Moreover, ribosomal sites and active nucleolus organizer regions from both parental contributors were found in the triploid hybrid. Considering the significant genetic distances between karyomorphs A and D, one of the primary reasons for the lack of recurrent reports of hybridization in the H. malabaricus species complex may be due to post-zygotic barriers, such as hybrid sterility or unviability. (C) 2014 The Fisheries Society of the British Isles