Revalidation and redescription of Triatoma brasiliensis macromelasoma Galvão, 1956 and an identification key for the Triatoma brasiliensis complex (Hemiptera: Reduviidae: Triatominae)

Triatoma brasiliensis macromelasoma is revalidated based on the results of previous multidisciplinary studies on the Triatoma brasiliensis complex, consisting of crossing experiments and morphological, biological, ecological and molecular analyses. These taxonomic tools showed the closest relationship between T. b. macromelasoma and Triatoma brasiliensis brasiliensis. T. b. macromelasoma is redescribed based on specimens collected in the type locality and specimens from a F1 colony. The complex now comprises T. b. brasiliensis, T. b. macromelasoma, Triatoma melanica, Triatoma juazeirensis and Triatoma sherlocki. An identification key for all members of the complex is presented. This detailed comparative study of the morphological features of T. b. macromelasoma and the remaining members of the complex corroborates results from multidisciplinary analyses, suggesting that the subspecific status is applicable. This subspecies can be distinguished by the following combination of features: a pronotum with 1+1 narrow brownish-yellow stripes on the submedian carinae, not attaining its apex, hemelytra with membrane cells darkened on the central portion and legs with an incomplete brownish-yellow ring on the apical half of the femora. Because the T. brasiliensis complex is of distinct epidemiological importance throughout its geographic distribution, a precise identification of its five members is important for monitoring and controlling actions against Chagas disease transmission.

Comparative study of the stridulatorium sulcus, buccula and rostrum of nymphs of Triatoma klugi Carcavallo et al, Triatoma vandae Carcavallo et al and Triatoma williami Galvão et al (Hemiptera: Reduviidae)

Ultrastructural analysis of the ventral region of the head - rostrum, buccula and stridulatorium sulcus - of 1st, 3rd and 5th instars of Triatoma klugi Carcavallo et al, Triatoma vandae Carcavallo et al, and Triatoma williami Galvão et al, are described in here. Morphological differences in the analyzed structures for all three Triatoma species studied were detected under scanning electron microscopy, allowing their grouping by their morphological similarities. Species-specific differences at each nymphal development stage were analyzed as well.

Descrição de Apiomerus costai sp. nov. do Mato Grosso, com notas taxonômicas sobre Apiomerus Hahn (Hemiptera, Heteroptera: Reduviidae, Harpactorinae, Apiomerini) / Description of Apiomerus costai sp. nov. from Mato Grosso State, Brazil, with taxonomical notes on Apiomerus Hahn (Hemiptera, Heteroptera: Reduviidae, Harpactorinae, Apiomerini)

Apiomerus costai sp. nov. (Hemiptera: Reduviidae) é descrita. Notas taxonômicas sobre Apiomerus Hahn são apresentadas.

Apiomerus costai sp. nov. (Hemiptera: Reduviidae) is described and taxonomical notes about Apiomerus Hahn are presented.

What does determine gonad weight in the wild kissing bug Mepraia spinolai

Female fecundity increases with body size in a variety of insects, but it is unknown if this generalization applies for kissing bugs. In this study, we evaluate whether gonad weight in the bloodsucking insect Mepraia spinolai correlates with body size, or determined by nutrition or developmental time. We found that the investment on reproductive tissue correlates positively and significantly with body size and with the amount of ingested blood by female insects along their lifespan. Total molting time did not significantly affect gonad weight. We suggest that under optimal feeding conditions M. spinolai females could express their maximum reproductive potential.

Internal reproductive organs of Cosmoclopius nigroannulatus (Hemiptera: Reduviidae)

Os órgãos internos de reprodução de machos e fêmeas de Cosmoclopius nigroannulatus são descritos, ilustrados e mensurados. Não se registrou diferença significativa entre machos imaturos e reprodutivos quanto ao tamanho das estruturas, sendo o aspecto destas similar em ambos. Já nas fêmeas, constataram-se diferenças notáveis tanto no aspecto quanto no tamanho.

Estudo biológico e morfométrico dos estádios ninfais de Rhodnius neglectus Lent, 1954 (Hemiptera, Reduviidae) / Biological and morphometrical study of instar nymphs of Rhodnius neglectus Lent, 1954 (Hemiptera, Reduviidae)

O estudo do ciclo biológico de Rhodnius neglectus à temperatura de 28ºC e umidade relativa do ar variando entre 52-94% revelou os seguintes parâmetros: a) período médio de incubação dos ovos: 13,67 dias; b) taxa de eclosão dos ovos: 86,18%; c) período médio de desenvolvimento do 1º, 2º, 3º, 4º e 5º estádios ninfais: 18,91; 15,19; 21,38; 21,34 e 30,43 dias, respectivamente; d) percentual de mortes nos estádios ninfais: 13,82; 18,26; 9,95; 8,78 e 15,06%, respectivamente; e) percentual de mudas por estádio ninfal; 86,18; 81,74; 90,05; 91,22 e 84,94%, respectivamente. O estudo morfométrico com microscópio estereoscópico e sistema de análise de imagem revelou que nos cinco estádios ninfais ocorre crescimento gradual das três principais divisões do corpo. Em todos estádios o abdômen é o maior segmento. Nos quatro primeiros estádios a cabeça é maior que o tórax. No quinto estádio a cabeça e o tórax apresentam portes equivalentes

Estudo da genitália externa masculina de duas espécies de Opisthacidius Berg, 1879 (Hemiptera, Reduviidae, Reduviinae) / Study of the male external genitalia of two species of Opisthacidius Berg, 1879

In order to stablish new taxonomic characters for the genus Opisthcidius a detailed comparative study of the male external genitalia was performed in O. rubropictus (H. Shaeffer, 1848), the type species, and O. pertinax (Breddin, 1903), mantioned as predators of triatomines. The most representative phallic structures were: the median process of pygophore, the phallosoma struts and the vesica process.