Triatoma tibiamaculata (Pinto, 1926): a classic Triatoma Laporte, 1832 or a Panstrongylus Berg, 1879 with homoplasms?

• Grant number: 20/08471-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2020
• End date: July 31, 2021
• Field of knowledge: Health Sciences - Collective Health - Public Health
• Principal Investigator: Kaio Cesar Chaboli Alevi
• Grantee: Giulia Montanari
• Host Institution: Faculdade de Ciências Farmacêuticas (FCFAR). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Triatomines are hematophagous insects of great epidemiological importance, as they act as vectors for the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. The genera Triatoma, Rhodnius and Panstrongylus are the most important from an epidemiological point of view. The genus Panstrongylus was initially considered as monophyletic from morphological data. Molecular data with the nuclear marker ITS-2 suggested the polyphilia of Panstrongylus spp. Subsequently, several phylogenetic analyzes demonstrated that the genus Panstrongylus is a paraphyletic group, since Pasntrongylus spp. was grouped with Nesotriatoma spp. and T. tibiamaculata in the P. megistus clade. The taxonomy of T. tibiamaculata was quite unstable, as it was initially described in the genus Eutriatoma, highlighting that it had intermediate characteristics between Rhodnius and Triatoma. In 1940, this species was grouped into the genus Triatoma and the subgenus Eutriatoma and, subsequently, E. tibiamaculata and T. (E.) tibiamaculata were synonymous with T. tibiamaculata. Although grouped in the genus Triatoma, the phylogenetic position of T. tibiamaculata in relation to the species of this genus has always been uncertain, since this triatomine was grouped in all phylogenies with the genera Panstrongylus and/or Nesotriatoma, rescuing T. tibiamacula and P. megistus as sister species. Thus, the present work aims to assess the generic status of T. tibiamaculata, through phylogenetic analysis, chromosomal measurement and experimental crosses.