Liliana Mola

Male meiosis was studied in a population of Acanonicus hahni (Stål), and nine of the sixteen individuals analyzed showed desynapsis. The frequency of univalents varied from one to seven percent in eight of them, while in the ninth the percentage of cells with univalents was higher (12%). The univalents auto-orientate at metaphase I in the center of the ring formed

Male meiosis was studied in a population of Acanonicus hahni (Stål), and nine of the sixteen individuals analyzed showed desynapsis. The frequency of univalents varied from one to seven percent in eight of them, while in the ninth the percentage of cells with univalents was higher (12%). The univalents auto-orientate at metaphase I in the center of the ring formed

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 = ...

... on adult males of E. meditabunda from Macomita (8 males) (Tucumán Province); Gilbert (4 males), Gualeguaychú (3 males), Almada (4 males), and Colόn (4 males) (Entre Ríos Province); Hughes (1 ... PABLO J. REBAGLIATI1l, ALBA G. PAPESCHI1,2 and LILIANA M. MOLA1,2 ...