Meiotic behavior of 18 species from eight families of terrestrial heteroptera.

Insects of the suborder Heteroptera are known for their odor, for being pests, or for being disease carriers. To gain better insight into the cytogenetic characteristics of heteropterans, 18 species of terrestrial Heteroptera belonging to eight families were studied. The presence of heteropycnotic corpuscles during prophase I, terminal or interstitial chiasmas, telomeric associations between chromosomes, ring disposals of autosomes during metaphase, and late migrations of the sex chromosomes during anaphase were analyzed. These features showed identical patterns to other species of Heteroptera previously described in the literature. Another studied characteristic was chromosome complements. The male chromosome complements observed were 2n = 12 chromosomes [10A + XY, Galgupha sidae (Amyot & Serville) (Corimelaenidae) and Pachycoris torridus (Scopoli) (Scutelleridae)]; 2n = 13 [10A + 2m + X0, Harmostes serratus (Fabricius), Harmostes apicatus (Stål), Jadera haematoloma (Herrich-Schaeffer), Jadera sanguinolenta (Fabricius), Jadera sp. (Rhopalidae)], and Neomegalotomus parvus (Westwood) (Alydidae); 2n = 13 [12A + X0, Stenocoris furcifera (Westwood) (Alydidae); 2n = 14 [12A + XY, Dictyla monotropidia (Stål) (Tingidae)]; 2n = 19 [18A + X0, Acanonicus hahni (Stål) (Coreidae)]; 2n = 21 [18A + 2m + X0, Acanthocephala sp. (Dallas) (Coreidae)]; 2n = 27 [24A + 2m + X0, Anisoscelis foliacea marginella (Dallas) (Coreidae)]; 2n = 18 [16A + XY, Oncopeltus fasciatus (Dallas) (Lygaeidae)]; 2n = 17 [14A + X1X2Y, Oxycarenus hyalinipennis (Costa) (Lygaeidae)]; 2n = 16 [12A + 2m + XY, Pachybrachius bilobatus (Say) (Lygaeidae)]; 2n = 26 [24A + XY, Atopozelus opsinus (Elkins) (Reduviidae)]; and 2n = 27 [24A + X1X2Y, Doldina carinulata (Stål) (Reduviidae)]. The diversity of the cytogenetic characteristics of Heteroptera was reflected in the 18 studied species. Thus, this study extends the knowledge of these characteristics, such as the variations related to chromosome complements, sex chromosome systems, and meiotic behavior.

Chromosomal divergence and evolutionary inferences in Pentatomomorpha infraorder (Hemiptera, Heteroptera) based on the chromosomal location of ribosomal genes.

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.

Meiotic chromosomes and nucleolar behavior in testicular cells of the grassland spittlebugs Deois flavopicta, Mahanarva fimbriolata and Notozulia entreriana (Hemiptera, Auchenorrhyncha).

Spittlebugs annually infest pastures and cause severe damage, representing a serious problem for the tropical American beef cattle industry. Spittlebugs are an important biotic constraint to forage production and there is a lack of cytogenetic data for this group of insects. For these reasons, we conducted this work, in which the spermatogenesis and nucleolar behavior of Deois flavopicta, Mahanarva fimbriolata and Notozulia entreriana were studied. The males possessed testes in the shape of a "bunch of grapes"; a variable number of testicular lobes per individual and polyploid nuclei composed of several heteropycnotic bodies. A heteropycnotic area was located in the periphery of the nucleus (prophase I); the chiasmata were terminal or interstitial; metaphases I were circular or linear and anaphase showed late migration of the sex chromosome. The chromosome complement had 2n = 19, except for N. entreriana (2n = 15); the spermatids were round with heteropycnotic material in the center and elongated with conspicuos chromatin. The analysis of testes after silver nitrate staining showed polyploid nuclei with three large and three smaller nucleolar bodies. Early prophase cells had an intensely stained nucleolar body located close to the chromatin and another less evident body located away from the chromatin. The nucleolar bodies disintegrated during diplotene. Silver staining occurred in two autosomes, in terminal and subterminal locations, the latter probably corresponding to the nucleolus organizer regions (NORs). The spermatids were round with a round nucleolar body and silver staining was observed in the medial and posterior region of the elongated part of the spermatid head.

Morphological aspects of the testes of 18 species of terrestrial of Heteroptera from Northwestern Sao Paulo (Brazil) / Aspectos testiculares de 18 especies terrestres de Heteroptera do Noroeste de Sao Paulo (Brasil)

The Heteroptera are known for their odour, for being pests or for being disease carriers. However, they are still not extensively studied, perhaps because they form a very large group. Therefore, with the aim of enhancing the knowledge of the morphology of the testes of this insect order, we collected and analysed 18 species of terrestrial Heteroptera from the northwestern part of São Paulo. The analysis of these species revealed some differences between the testicles of these species, including their shape (elongated, oval, round or pecten), the morphology of the testicular lobes (elongated and paired side by side or united in a single region), the colours of the peritoneal sheath that surrounds the lobes (red, orange, yellow or translucent), and the number of testicular lobes (one, two, four, five, six or seven). Because the aspects analysed were highly variable, our study suggests a need for further analysis of Heteropteran testicular morphological differences.

Os Heteroptera são organismos conhecidos pelo seu odor, por serem pragas ou por serem transmissores de doenças, contudo, eles ainda são pouco estudados, talvez por formarem um grupo muito grande. Portanto, com o objetivo de ampliarmos as informações dos aspectos testiculares deste grupo analisamos 18 espécies de Heteroptera terrestres pertencentes a oito famílias que foram coletadas no Noroeste Paulista. Através das análises dessas espécies foi observado diferenças testiculares quanto: a sua forma (alongadas; ovalados; forma de concha, denominada pecten; ou arredondados); a morfologia dos lobos (alongados e pareados lado a lado ou unidos em uma única região, na forma de um “ofiuroide”); às cores da bainha peritoneal (alaranjada, amarelada, avermelhada ou transparente); ao número de lobos testiculares (um, dois, quatro, cinco, seis, sete). Devido aos aspectos analisados serem muito variáveis, nosso estudo sugere um aprofundamento maior na questão que envolve as diferenças morfológicas testiculares.

Checklist and description of three new chromatic patterns of Pachycoris torridus (Scopoli, 1772) (Hemiptera: Scutelleridae)

In the present paper, 27 chromatic patterns of the specie Pachycoris torridus (Scopoli, 1772) were grouped and three new patterns are described. Because of this high phenotypic polymorphism, P. torridus already been registered eight times as a new specie, highlighting the importance of the application of different tools to assist in taxonomy of this hemipterous of economic importance.

No presente artigo, 27 padro˜ es croma´ ticos da espe´cie Pachycoris torridus (Scopoli, 1772) sa˜o agrupados e treˆs novos padro˜ es sa˜o descritos. Devido a esse grande polimorfismo fenoti´pico, P. torridus ja´ foi registrado oito vezes como espe´cie nova, o que ressalta a importaˆncia da aplicac¸a˜o de diferentes ferramentas para auxiliar na taxonomia desse hemi´ptero de importaˆncia econoˆmica.

Meiotic chromosomes and nucleolar behavior in testicular cells of the grassland spittlebugs Deois flavopicta, Mahanarva fimbriolata and Notozulia entreriana (Hemiptera, Auchenorrhyncha)

Spittlebugs annually infest pastures and cause severe damage, representing a serious problem for the tropical American beef cattle industry. Spittlebugs are an important biotic constraint to forage production and there is a lack of cytogenetic data for this group of insects. For these reasons, we conducted this work, in which the spermatogenesis and nucleolar behavior of Deois flavopicta, Mahanarva fimbriolata and Notozulia entreriana were studied. The males possessed testes in the shape of a "bunch of grapes"; a variable number of testicular lobes per individual and polyploid nuclei composed of several heteropycnotic bodies. A heteropycnotic area was located in the periphery of the nucleus (prophase I); the chiasmata were terminal or interstitial; metaphases I were circular or linear and anaphase showed late migration of the sex chromosome. The chromosome complement had 2n = 19, except for N. entreriana (2n = 15); the spermatids were round with heteropycnotic material in the center and elongated with conspicuos chromatin. The analysis of testes after silver nitrate staining showed polyploid nuclei with three large and three smaller nucleolar bodies. Early prophase cells had an intensely stained nucleolar body located close to the chromatin and another less evident body located away from the chromatin. The nucleolar bodies disintegrated during diplotene. Silver staining occurred in two autosomes, in terminal and subterminal locations, the latter probably corresponding to the nucleolus organizer regions (NORs). The spermatids were round with a round nucleolar body and silver staining was observed in the medial and posterior region of the elongated part of the spermatid head.

Morphological patterns of the heteropycnotic chromatin and nucleolar material in meiosis and spermiogenesis of some Pentatomidae (Heteroptera)

Pentatomidae is a family of Heteroptera which includes several agriculture pests that have had different aspects of their meiosis and spermiogenesis analyzed. In the present study we analyzed the morphological patterns of the heteropycnotic chromatin and the nucleolar material of Mormidea v-luteum, Oebalus poecilus and Oebalus ypsilongriseus. The three species presented multilobate testes, with three lobes in M. v-luteum and four in the Oebalus species. A karyotype with 2n = 14 chromosomes (12A + XY) was observed in the three species. Several characteristics were common to the three species, such as the absence of a testicular harlequin lobe (a lobe which produces different types of spermatozoa, previously considered a general characteristic of this family), late migration of the sex chromosomes and semi-persistence of the nucleolus. The three species also shared some characteristics regarding the patterns of the heteropycnotic chromatin and nucleolar material, but differed in others mainly related to the location of the heteropycnotic chromatin in the spermatids and the morphology and distribution of the nucleolar material at zygotene. The differences were always between species from different genera, suggesting a relationship with their genetic divergence.

Effects of caffeine on fecundity, egg laying capacity, development time and longevity in Drosophila prosaltans

Quatro concentraçöes de cafeína (t0=50 ug/ml, t1=100 ug/ml) foram administradas, no meio de cultura, a Drosophila prosaltans, objetivando detectar possíveis efeitos sobre a fecundidade, a oviposiçäo, a longevidade dos adultos e a velocidade do desenvovlimento ovo-adulto. Os resultados mostraram(a) reduçäo da fecundidade em todas as concentraçöes, numa relaçäo direta dose-efeito, (b) aumento em um dia do tempo de desenvolvimento nas concentraçöes 1000 e 1500 ug/ml (c) reduçäo da oviposiçäo, também em relaçäo direta à concentraçäo de cafeína no meio e (d) reduçäo da longevidade das fêmeas e machos cruzadas, tratadas, mostraram, na maioria dos experimentos, maior longevidade que o controle, sugerindo um certo benefício do bloqueio parcial da oviposiçäo, causado pela cafeína