Home » Volumes » Volume 51 January/February 2018 » First report of Triatoma sordida Stål, 1859 (Hemiptera, Reduviidae, Triatominae) in the State of Acre and Brazilian Western Amazon

First report of Triatoma sordida Stål, 1859 (Hemiptera, Reduviidae, Triatominae) in the State of Acre and Brazilian Western Amazon

Leandro José Ramos1 2 Janis Lunier de Souza3 Cláudio Rodrigues de Souza3 Jader de Oliveira 4 5 João Aristeu da Rosa4 5 Luis Marcelo Aranha Camargo6 7 8 9 Renildo Moura da Cunha2 10 11 Dionatas Ulises de Oliveira Meneguetti7 10 12

1Centro de Ciências da Saúde e do Desporto, Universidade Federal do Acre, Rio Branco, AC, Brasil. 2Programa de Pós Graduação Stricto Sensu em Biodiversidade e Biotecnologia da Amazônia Legal, Universidade Federal do Acre, Rio Branco, AC, Brasil. 3Departamento de Entomologia da Secretaria Estadual de Saúde, Rio Branco, AC, Brasil. 4Departamento de Ciências Biológicas, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista Júlio de Mesquita Filho, Araraquara, SP, Brasil. 5Programa de Pós Graduação Stricto Sensu em Biociências e Biotecnologia, Universidade Estadual Paulista Júlio de Mesquita Filho, Araraquara, SP, Brasil. 6. Instituto de Ciências Biomédicas-5, Universidade de São Paulo, Monte Negro, RO, Brasil. 7Programa de Pós Graduação Stricto Sensu em Ciência da Saúde na Amazônia Ocidental, Universidade Federal do Acre, Rio Branco, AC, Brasil. 8Departamento de Medicina, Faculdade São Lucas, Porto Velho, RO, Brasil. 9Centro de Pesquisas em Medicina Tropical, Porto Velho, RO, Brasil. 10Programa de Pós Graduação Stricto Sensu em Ciência, Inovação e Tecnologia para a Amazônia, Universidade Federal do Acre, Rio Branco, AC, Brasil. 11Centro de Ciências Biológicas e da Natureza, Universidade Federal do Acre, Rio Branco, AC, Brasil. 12Colégio de Aplicação, Universidade Federal do Acre, Rio Branco, AC, Brasil.

DOI: 10.1590/0037-8682-0161-2017

In the Brazilian Amazon, there are at least 20 species of wild triatomines



The occurrence of Triatoma sordida in the Brazilian Western Amazon is reported for the first time.


Triatoma sordida specimens were collected from a Gallus gallus nest in a peridomiciliary area of Senador Guiomard municipality in the state of Acre.


The number of triatomine species in Acre increased from six to seven with this first report of T. sordida in the Brazilian Western Amazon.


The occurrence of T. sordida in Acre is of concern since it is among the most captured triatomines in peridomiciliary environments in Brazil, and carries a high potential for vector transmission.

Keywords: Triatomines; Chagas disease; Trypanosomatids

Triatominae (Hemiptera, Reduviidae, Triatominae) are insects of medical importance, since they can transmit Trypanosoma cruzi, the etiologic agent of American trypanosomiasis, also known as Chagas disease1, which affects approximately 12 million people, with a further 60 million people living in areas of risk around the world2.

In the Brazilian Amazon, there are at least 20 species of wild triatomines3, among which six species distributed in three genera are recorded in the state of Acre: Rhodnius montenegrensis4Rhodnius stali5R. robustus6R. pictipesPanstrongylus geniculatus3, and Eratyrus mucronatus7.

This study reports for the first time the occurrence of the species Triatoma sordida in the state of Acre and the Brazilian Western Amazon; this is also the first record of the genus Triatoma for the State of Acre.

Two specimens, adult T. sordida males (Figure 1), were collected at the Catuaba Experimental Reserve, Senador Guiomard, Acre, Brazil (10° 09ʹ 03ʹʹ S 67° 44ʹ 09ʹʹ W), an area belonging to the Federal University of Acre (UFAC). The insects were collected during May 2016, through active searches in Gallus gallus nests in the peridomiciliary area of an old farm house, built with wood and covered with palm tree thatching. The building is situated in the middle of a secondary forest fragment, surrounded by palms of the genera AttaleaEuterpe, and Bactris.

FIGURE 1: Triatoma sordida collected in the Catuaba Experimental Reserve. (A and B): dorsal view; (C and D): ventral view. 

The triatomines were sent to the Laboratory of Tropical Medicine (LABMEDT) at UFAC, where the taxonomic identification was carried out based on external morphological characteristics, as described by Lent and Wygodzinsky8. Trypanosomatid infection was also analyzed by diluting the triatomine feces in saline solution, preparing them on microscope slides, and then examining them under light microscopy (1,000× magnification) after staining with triarylmethane (0.1%), xanthene (0.1%), and thiazine (0.1%).

The occurrence of this species in nests is already known, as it has recently been found in bird and mammal nests in the Brazilian Pantanal region2,9. However, the discovery in poultry nests, such as those of G. gallus, generates a concern due both to the proximity of these animals to humans, especially species that have a high frequency of infection by T. cruzi10, and the findings of the present study, because the two specimens collected tested positive for trypanosomatids, although no molecular analysis was performed to confirm the species.

Three adult specimens of T. sordida (Figure 2), two males and one female, were located in the entomological collection of the Department of Entomology of the State Department of Health, Acre, but they had been mistakenly identified as Triatoma matogrossensis. According to the Department’s registry, these specimens were collected and delivered by residents living in the periurban region of the municipality of Rio Branco, Acre, from the Calafate neighborhood, but with no exact description of the locality or date of collection.

FIGURE 2: Specimens of Triatoma sordida stored in the Department of Entomology of the State Health Department of Acre. (A):dorsal view; (B)(C) and (D):: ventral view. 

The presence of another species of triatomine occurring in Acre increases the total number of species in the state from six to seven, and the number of genera from three to four. The new record also increases the geographic distribution of T. sordida, since it has been described for the states of Bahia, Goiás, Maranhão, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Paraná, Pernambuco, Piauí, Rio Grande do Sul, Santa Catarina, São Paulo, and Tocantins3,10.

Although T. sordida is not reported to occur in the states neighboring Acre (Rondônia and Amazonas), this species does occur in Bolívia11, a country neighboring Acre. A study carried out in Velasco Province in the north of the Department of Santa Cruz, Bolívia, showed that 58% of the residences were occupied by T. sordida, 21.4% of which were infected by T. Cruzi12. This domiciliation behavior has also been observed in other regions of the Department of Santa Cruz, La Paz, and the Bolivian Chaco region13,14.

This new report for Acre is worrying, because T. sordida is considered the most frequently captured species in peridomiciliary environments in Brazil10. When evaluating the rate at which T. sordida is infected by T. cruzi, it has been observed that this species and Triatoma infestansTriatoma brasiliensisTriatoma pseudomaculata, and Panstrongylus megistus are the five species with the highest participation in home transmission of American trypanosomiasis10,15. Vigilance services must remain active in order to prevent the wider dispersion of T. sordidain western Amazonia, given the spread of Chagas disease in this region.

Ethical considerations

The specimens were collected with permission from the Brazilian Institute of Environment and Renewable Natural Resources [Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis (IBAMA)]; permanent license Nr. 52260-1.


The authors are grateful to Fundação de Amparo à Pesquisa do Estado do Acre (FAPAC) for the financial assistance and Pró-Reitoria de Pesquisa e Pós-Graduação da Universidade Federal do Acre (UFAC), for help in translation into English.


1. Meneguetti DUO, Trevisan O, Camargo LMA, Rosa RM. Natural infection of triatomines (Hemiptera: Reduviidae) by trypanosomatids in two different environments in the municipality of Ouro Preto do Oeste – Rondônia, Brazil. Rev Soc Bras Med Trop. 2012;45(3):395-8. [ Links ]

2. Santos FM, Jansen AM, Mourão GM, Jurberg J, Nunes AP, Herrera HM. Triatominae (Hemiptera, Reduviidae) in the Pantanal region: association with Trypanosoma cruzi, different habitats and vertebrate hosts. Rev Soc Bras Med Trop . 2015;48(5):532-8. [ Links ]

3. Gurgel-Gonçalves R, Galvão C, Costa J, Peterson AT. Geographic distribution of Chagas disease vectors in Brazil based on ecological niche modeling. J Trop Med. 2012;2012:1-15. doi: 10.1155/2012/705326. [ Links ]

4. Meneguetti DUO, Tojal SD, Miranda PRM, Rosa JA, Camargo LMA. First report of Rhodnius montenegrensis(Hemiptera, Reduviidae, Triatominae) in the State of Acre, Brazil. Rev Soc Bras Med Trop . 2015;48(4):471-3. [ Links ]

5. Meneguetti DUO, Castro GVS, Castro MALR, Souza JL, Oliveira J, Rosa JA, et al. First report of Rhodnius stali(Hemiptera, Reduviidae, Triatominae) in the State of Acre and in the Brazilian Amazon. Rev Soc Bras Med Trop . 2016;49(3):365-8. [ Links ]

6. Barata JMS, Rocha RM, Rodrigues VLCC, Ferraz-Filho AN. Primeiro caso autóctone de tripanossomíase americana no Estado do Acre (Brasil) e sua correlação com as cepas isoladas do caso humano e de triatomíneos silvestres da área. Rev Saude Publica. 1988;22(5):401-10. [ Links ]

7. Obara MT, Cardoso AS, Pinto MCG, Souza CR, Silva RA, Gurgel-Gonçalves R. Eratyrus mucronatus Stål, 1859 (Hemiptera: Reduviidae: Triatominae): First report in the State of Acre, Brazil, and updated geographic distribution in South America. Check List. 2013;9(4):851-4. [ Links ]

8. Lent H, Wygodzinsky PW. Revision of the Triatominae (Hemiptera, Reduviidae), and their significance as vectors of Chagas’ disease. Bull Am Mus Nat Hist. 1979;163(3):127-520. [ Links ]

9. Lima JS, Rocha FL, Alves FM, Lorosa ES, Jansen AM, Mourão GM. Infestation of arboreal nests of coatis by triatomine species, vectors of Trypanosoma cruzi, in a large Neotropical wetland. J Vector Ecol. 2015;40(2):379-85. [ Links ]

10. Galvão C. Vetores da doença de Chagas no Brasil. Curitiba: Sociedade Brasileira de Zoologia; 2014. 289p. [ Links ]

11. Brenière SF, Morochi W, Bosseno MF, Ordoñez J, Gutierrez T, Vargas F, et al. Trypanosoma cruzi genotypes associated with domestic Triatoma sordida in Bolivia. Acta Trop. 1998;71(3):269-83. [ Links ]

12. Noireau F, Brenière F, Ordoñez J, Cardozo L, Morochi W, Gutierrez T, et al. Low probability of transmission of Trypanosoma cruzi to humans by domiciliary Triatoma sordida in Bolivia. Trans R Soc Trop Med Hyg. 1997;91(6):653-6. [ Links ]

13. Noireau F, Gutierrez T, Zegarra M, Flores R, Brenière F, Cardozo L, et al. Cryptic speciation in Triatoma sordida (Hemiptera:Reduviidae) from the Bolivian Chaco. Trop Med Int Health. 1998;3(5):364-72. [ Links ]

14. Noireau F, Gutierrez T, Flores R, Breniere F, Bosseno MF, Wisnivesky-Colli C. Ecogenetics of Triatoma sordidaand Triatoma guasayana (Hemiptera: reduviidae) in the Bolivian chaco. Mem Inst Oswaldo Cruz. 1999;94(4):451-7. [ Links ]

15. Silveira AC, Rezende DF. Epidemiologia e controle da transmissão vetorial da doença de Chagas no Brasil. Rev Soc Bras Med Trop . 1984;27(suppl. III):11-22. [ Links ]

Financial support: Programa Pesquisa Para o SUSGestão Compartilhada em Saúde (PPSUS) 001/2015 – Fundação de Amparo à Pesquisa do Estado do Acre (FAPAC).

Received: April 28, 2017; Accepted: September 18, 2017

Corresponding author: Dr. Dionatas Ulises de Oliveira Meneguetti. e-mail:dionatas@icbusp.org

Conflict of interests: The authors declare that there is no conflict of interest.