title: Towards a phylogenetic approach to the composition of species complexes in the North and Central American Triatoma, vectors of Chagas disease.
abstract: Phylogenetic relationships of insect vectors of parasitic diseases are important for understanding the evolution of epidemiologically relevant traits, and may be useful in vector control. The sub-family Triatominae (Hemiptera:Reduviidae) includes ∼140 extant species arranged in five tribes comprised of 15 genera. The genus Triatoma is the most species-rich and contains important vectors of Trypanosoma cruzi, the causative agent of Chagas disease. Triatoma species were grouped into complexes originally by morphology and more recently with the addition of information from molecular phylogenetics (the four-complex hypothesis); however, without a strict adherence to monophyly. To date, the validity of proposed species complexes has not been tested by statistical tests of topology. The goal of this study was to clarify the systematics of 19 Triatoma species from North and Central America. We inferred their evolutionary relatedness using two independent data sets: the complete nuclear internal transcribed spacer-2 ribosomal DNA (ITS-2 rDNA) and head morphometrics. In addition, we used the Shimodaira-Hasegawa statistical test of topology to assess the fit of the data to a set of competing systematic hypotheses (topologies). An unconstrained topology inferred from the ITS-2 data was compared to topologies constrained based on the four-complex hypothesis or one inferred from our morphometry results. The unconstrained topology represents a statistically significant better fit of the molecular data than either the four-complex or the morphometric topology. We propose an update to the composition of species complexes in the North and Central American Triatoma, based on a phylogeny inferred from ITS-2 as a first step towards updating the phylogeny of the complexes based on monophyly and statistical tests of topologies.
authors.affiliation: University of Vermont, Burlington, VT, USA.
authors.forename: Nicholas M
authors.initials: NM
authors.lastname: de la Rúa
authors.affiliation: Universidad de San Carlos, Guatemala City, Guatemala.
authors.forename: Dulce M
authors.initials: DM
authors.lastname: Bustamante
authors.affiliation: Universidad de San Carlos, Guatemala City, Guatemala.
authors.forename: Marianela
authors.initials: M
authors.lastname: Menes
authors.affiliation: University of Vermont, Burlington, VT, USA.
authors.forename: Lori
authors.initials: L
authors.lastname: Stevens
authors.affiliation: Universidad de San Carlos, Guatemala City, Guatemala.
authors.forename: Carlota
authors.initials: C
authors.lastname: Monroy
authors.affiliation: University of Vermont, Burlington, VT, USA.
authors.forename: C William
authors.initials: CW
authors.lastname: Kilpatrick
authors.affiliation: University of Vermont, Burlington, VT, USA.
authors.forename: Donna
authors.initials: D
authors.lastname: Rizzo
authors.affiliation: University of Arizona, Tucson, AZ, USA.
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Klotz
authors.affiliation: Southwestern Biological Institute, Tucson, AZ, USA.
authors.forename: Justin
authors.initials: J
authors.lastname: Schmidt
authors.affiliation: University of Vermont, Burlington, VT, USA.
authors.forename: Heather J
authors.initials: HJ
authors.lastname: Axen
authors.affiliation: Loyola University New Orleans, New Orleans, LA, USA. Electronic address: dorn@loyno.edu.
authors.forename: Patricia L
authors.initials: PL
authors.lastname: Dorn
mesh_terms: D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D014355:Chagas Disease / Q000635:transmission*; D004275:DNA, Ribosomal / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000235:genetics*; D004199:Disease Vectors / Q000145:classification; D014644:Genetic Variation; D007303:Insect Vectors / Q000145:classification / Q000235:genetics; D010802:Phylogeny; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D014224:Triatoma / Q000145:classification* / Q000235:genetics* / Q000469:parasitology; D014349:Trypanosoma cruzi / Q000472:pathogenicity
chemical_list: D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer
keywords: Chagas disease; ITS-2; Morphometry; Species complexes; Systematics; Triatominae