[Triatoma rubrovaria (Blanchard 1843): life table of nymphs, duration of the forms and posture of the females]

Triatoma rubrovaria (Hemiptera, Reduviidae, Triatominae) in the Pampa biome, Brazil: a retrospective study of its occurrence and abundance

Triatoma rubrovaria has been captured in some areas of Rio Grande do Sul State (RS), Brazil, as this species can be found in the Pampa biome. Its distribution across this biome should be described in detail to verify the potential of this vector to transmit Trypanosoma cruzi. This study aimed to investigate the occurrence of T. rubrovaria in the Pampa biome and transitional areas of RS. The collected information resulted from the analysis of secondary data provided by the Centro Estadual de Vigilancia em Saude (CEVS - State's Center of Health Surveillance). The following aspects were taken into consideration: the year in which the insect was captured, the city, the number of specimens captured, invasion or domiciliation, the notification in the household, surroundings or both, and T. cruzi infection. The data comprised the period from 2009 to 2020, in 109 cities located in the Pampa biome and 98 located in transitional areas. The Pampa biome exhibited 85% of the occurrences of T. rubrovaria, while 1.2% of specimens were T. cruzi-like positive. Both the first and second biennia concentrated 64.6% of captures. Alegrete city, Cangucu city and Piratini city were the locations in the Pampa where the largest numbers of specimens were found. Regarding the transitional areas, Roque Gonzales city, Santiago city and Santana da Boa Vista city exhibited the largest numbers. Most insects were adults, which were found in households. Even though positivity for T. cruzi-like was low, the species still has epidemiological importance in the region.

Characterization of the Buccula, Rostrum, Stridulatory Sulcus, Scutellum, and External Female Genitalia of Triatoma carcavalloi (Jurberg, Rocha & Lent, 1998), Triatoma circummaculata (Stål, 1859), and Triatoma rubrovaria (Blanchard, 1843) (Hemiptera, Reduviidae, Triatominae)

In Brazil, Triatoma rubrovaria (Blanchard, 1843) is the most important species in epidemiological terms in the State of Rio Grande do Sul, due to its wide geographical distribution in this state, followed by T. carcavalloi (Jurberg, Rocha & Lent, 1998) and T. circummaculata (Stål, 1859). Structural analysis of the ventral region of the head (rostrum and buccula), thorax (stridulatorium sulcus and scutellum), and external female genitalia of adults of T. rubrovaria, T. carcavalloi, and T. circummaculata is described here. Scutellum, head, rostrum, and part of the thorax (prosternum) containing the stridulatory sulcus, in both male and female, and the sixth abdominal segment of the female, containing the external genitalia, were processed for scanning electron microscopy studies as routine. Morphological differences in the analyzed structures for all the three Triatoma species studied were detected under scanning electron microscopy. This study confirms the grouping of the T. rubrovaria, T. carcavalloi, and T. circummaculata in 'T. rubrovaria subcomplex' by their morphological similarities.