Research Article

Cytogenetic analysis of Triatoma pseudomaculata Corrêa and Espínola, 1964 (Hemiptera, Triatominae) from different Brazilian states

Published: March 31, 2016
Genet. Mol. Res. 15(1): gmr6937 DOI: https://doi.org/10.4238/gmr.15016937
Cite this Article:
C.H.L. Imperador, K.C.C. Alevi, J. Oliveira, J.A. Rosa, M.T.V. Azeredo-Oliveira, C.H.L. Imperador, K.C.C. Alevi, J. Oliveira, J.A. Rosa, M.T.V. Azeredo-Oliveira, C.H.L. Imperador, K.C.C. Alevi, J. Oliveira, J.A. Rosa, M.T.V. Azeredo-Oliveira (2016). Cytogenetic analysis of Triatoma pseudomaculata Corrêa and Espínola, 1964 (Hemiptera, Triatominae) from different Brazilian states. Genet. Mol. Res. 15(1): gmr6937. https://doi.org/10.4238/gmr.15016937
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Abstract

Triatoma maculata and T. pseudomaculata are allopatric; however, it is believed that T. maculata was introduced into the Brazilian northeast by passive transportation of the nymphs between the feathers of migratory birds, followed by the speciation of T. pseudomaculata. T. pseudomaculata is the second most epidemiologically important species in the northeast of Brazil after T. brasiliensis. Therefore, given the broad range of T. pseudomaculata, the objective of the present study was to cytogenetically analyze different populations of T. pseudomaculata from different Brazilian states in order to investigate possible intraspecific chromosomal variation between them. Three adult T. pseudomaculata males from each population (Pernambuco, Ceará, Paraíba, Bahia, Rio Grande do Norte, and Piauí) were analyzed by lacto-acetic orcein and C-banding. All of the specimens analyzed exhibited the same cytogenetic characteristics, i.e., 22 chromosomes (20 autosomes and XY), a chromocenter formed by the X and Y sex chromosomes and one pair of autosomes, and heterochromatin blocks in three or four pairs of autosomes. These data confirm that all of the populations analyzed were T. pseudomaculata, and although they may be subject to different selection pressures they have maintained the genetic integrity that characterizes the species.

Triatoma maculata and T. pseudomaculata are allopatric; however, it is believed that T. maculata was introduced into the Brazilian northeast by passive transportation of the nymphs between the feathers of migratory birds, followed by the speciation of T. pseudomaculata. T. pseudomaculata is the second most epidemiologically important species in the northeast of Brazil after T. brasiliensis. Therefore, given the broad range of T. pseudomaculata, the objective of the present study was to cytogenetically analyze different populations of T. pseudomaculata from different Brazilian states in order to investigate possible intraspecific chromosomal variation between them. Three adult T. pseudomaculata males from each population (Pernambuco, Ceará, Paraíba, Bahia, Rio Grande do Norte, and Piauí) were analyzed by lacto-acetic orcein and C-banding. All of the specimens analyzed exhibited the same cytogenetic characteristics, i.e., 22 chromosomes (20 autosomes and XY), a chromocenter formed by the X and Y sex chromosomes and one pair of autosomes, and heterochromatin blocks in three or four pairs of autosomes. These data confirm that all of the populations analyzed were T. pseudomaculata, and although they may be subject to different selection pressures they have maintained the genetic integrity that characterizes the species.