ISSN:
1573-6849
Keywords:
Dysdercus albofasciatus
;
Heteroptera
;
holokinetic chromosomes
;
neo-XY
;
Pyrrhocoridae
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The genus Dysdercus Guérin Méneville 1831 represents the only taxon within the family Pyrrhocoridae in the New World. Based on morphological features, it has been suggested that American species derived from immigrants from the Old World, most probably from the Ethiopian Region. So far, 10 species from Dysdercus, including six species from the Old World and four species from the Neotropical Region have been cytogenetically analyzed. As is characteristic of Heteroptera, they possess holokinetic chromosomes and a prereductional type of meiosis. While the X1X20 sex chromosome system has been reported in all cytologically analyzed species of Dysdercus from the Old World, the system X0 has been found in all but one species from the New World, regardless of the number of autosomes in the complement. In the present study the male meiosis of D. Albofasciatus Berg 1878 was studied in specimens from four different populations from Argentina. The diploid chromosome number was found to be 2n = 10 + neo-XY. The neo-X shows at each subterminal region a positively heteropycnotic and DAPI-bright segment which corresponds to the ancestral X-chromosome. The origin of this neo-XY system involved, most probably, a subterminal insertion of the ancestral X chromosome in an autosome, followed by a large inversion, which included part of the original X chromosome.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1009262210338
Permalink
