With the objective of assisting in the understanding of the chromosome evolution of Pentatomomorpha and in the quest to understand how the genome organizes/reorganizes for the chromosomal position of the 45S rDNA in this infraorder, we analyzed 15 species (it has being 12 never studied before by FISH) of Pentatomomorpha with the probe of 18S rDNA. The mapping of the 45S gene in the Coreidae family demonstrated that the species presented markings on the autosomes, with the exception of Acanthocephala parensis and Leptoglossus gonagra that showed markers on m-chromosomes. Most species of the Pentatomidae family showed marking in the autosomes, except for two species that had 45S rDNA on X sex chromosome (Odmalea sp. and Graphosoma lineatum) and two that showed marking on the X and Y sex chromosomes. Species of the Pyrrhocoridae family showed 18S rDNA markers in autosomes, X chromosome as well as in Neo X. The Largidae and Scutelleridae families were represented by only one species that showed marking on the X sex chromosome and on a pair of autosomes, respectively. Based on this, we characterized the arrangement of 45S DNAr in the chromosomes of 12 new species of Heteroptera and discussed the main evolutionary events related to the genomic reorganization of these species during the events of chromosome and karyotype evolution in Pentatomomorpha infraorder.

ABSTRACT. Few cytogenetic studies have been undertaken using aquatic heteropterans and the nucleolar behavior of these insects has been described in only four species, Limnogonus aduncus, Brachymetra albinerva, Halobatopsis platensis, and Cylindrostethus palmaris. The nucleolus is a cellular structure related to biosynthetic 8989 Nucleolar behavior in Martarega brasiliensis ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 14 (3): 8988-8994 (2015) activity and it exhibits a peculiar behavior in the heteropterans of the Triatominae subfamily; it persists during all stages of meiosis. Thus, this study aims to analyze spermatogenesis in Martarega brasiliensis, with an emphasis on nucleolar behavior. Twenty M. brasiliensis adult males were used and collected from the Municipal reservoir in the city of São José do Rio Preto, São Paulo, Brazil. The species were fixed in methanol:acetic acid (3:1), then dissected, and the testicles were extracted, torn apart, and impregnated with silver ions. During prophase, the nuclei of M. brasiliensis were composed of the nucleolus and nucleolar corpuscles, which varied in number from one to four, emphasizing that this insect has great synthetic activity during meiosis. The analysis of cells in metaphase I showed that M. brasiliensis presents a nucleolar organizing region in at least one autosome. Furthermore, the phenomenon of nucleolar persistence was not observed. All spermatids presented nucleolar markings that varied in number and position according to the stage of elongation. Moreover, it was also possible to highlight the presence of a vesicle in spermatids. Thus, this paper describes the nucleolar behavior of M. brasiliensis and highlights important characteristics during spermatogenesis, thus, increasing the knowledge about the biology of these aquatic heteropterans.

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ABSTRACT. The stink bug Pachycoris torridus is a pest of great agricultural importance due to its records on culture of physic nut (Jatropha curcas), which is the raw material for biodiesel production. An interesting feature of this insect is its high phenotypic variability, a characteristic that resulted in it being classified as a new species on eight separate occasions. In the suborder Heteroptera, the heterochromatin pattern is specific and often allows species to be differentiated. To confirm whether there is differentiation between specimens of P. torridus with different color patterns (yellow, orange, brown, and red), samples were analyzed cytogenetically using the C-banding method. During meiotic prophase, the four color patterns analyzed showed a large heterochromatic 15750 T.S. Souza-Firmino et al.©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 14 (4): 15749-15753 (2015) chromocenter, consisting of a combination of both sex chromosomes (X and Y). Thus, the present study reports chromosomal homogeneity in different color patterns of P. torridus and highlights the importance of this tool in the description of new species.

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