Mem Inst Oswaldo Cruz, Rio de Janeiro, Vol. 121 (Suppl. 2) 2026
Research Articles
Antennal sensilla phenotypes in the Triatoma brasiliensis species complex and their eco-epidemiological implications
1Universidade Federal do Rio de Janeiro, Instituto de Biofísica Carlos Chagas Filho, Laboratório de Parasitologia Molecular, Rio de Janeiro, RJ, Brasil
2Fundação Oswaldo Cruz-Fiocruz, Instituto Oswaldo Cruz, Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos, Rio de Janeiro, RJ, Brasil
3Smithsonian Institution, National Museum of Natural History, Department of Entomology, Washington (DC), United States of America
4Universidade Estadual Paulista, Faculdade de Ciências Farmacêuticas, Laboratório de Parasitologia, Araraquara, SP, Brasil
5Fundação Oswaldo Cruz-Fiocruz, Laboratório de Vigilância Entomológica, Teresina, PI, Brasil
DOI: 10.1590/0074-02760260114
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ABSTRACT
BACKGROUND The semi-arid region of Brazil is endemic for Chagas disease (CD) and therefore requires extensive vector surveillance and control efforts. The Triatoma brasiliensis complex comprises species that, due to their wide geographic distribution and high capacity for domiciliary infestation, are among the main vectors of Trypanosoma cruzi in that region. Previous studies suggest that antennal sensilla phenotypes may reflect environmental adaptations and influence vectorial capacity in triatomines.
OBJECTIVES In this context, the present study aimed to describe and compare the antennal sensilla of different species within the T. brasiliensis complex and to relate these patterns to each species ecological traits already recorded in the literature.
METHODS A total of 56 antennae, including males and females of T. b. brasiliensis, T. b. macromelasoma, T. bahiensis, T. juazeirensis, T. melanica, T. lenti, T. petrocchiae, and T. sherlocki, were analyzed. Using scanning electron microscopy, six types of sensilla were identified: bristle (BRT), campaniform (CAM), trichoid (TRD), coeloconic (COE), trichobothrium (TBT), and basiconic (BAS).
FINDINGS Species exhibiting greater diversity and abundance of sensilla showed higher ecological plasticity and were more frequently associated with anthropogenic environments, whereas species with lower sensillar diversity were more restricted to natural ecotopes.
MAIN CONCLUSIONS These findings indicate that antennal sensilla profiles may serve as important morphofunctional indicators of synanthropy and vectorial potential, contributing to a better understanding of the risk of CD transmission.
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Financial support: The third author (APS) was partially funded by the CAPES (Finance Code 001).
LPD, JPSO-C contributed equally to this work.
+ Corresponding author: jcosta@ioc.fiocruz.br | 
https://orcid.org/0000-0001-6664-1394
Received 27 March 2026
Accepted 20 May 2026
HOW TO CITE
Paschoaletto L, Oliveira-Correia JPS, Seabra AP, de Oliveira J, Nascimento JD, da Rosa JA, et al. Antennal sensilla phenotypes in the Triatoma brasiliensis species complex and their eco-epidemiological implications. Mem Inst Oswaldo Cruz. 2026; 121: e260114.
Handling editor: Carolina Dale | https://orcid.org/0000-0002-9526-9242
