Relationship between genetic diversity and morpho-functional characteristics of flight-related traits in Triatoma garciabesi (Hemiptera: Reduviidae).

VERLY THAIANE; PITA SEBASTIAN; CARBAJAL DE LA FUENTE ANA LAURA; BURGEÑO GABRIELA; PICCINALI ROMINA VALERIA; FIAD FEDERICO GASTÓN; RÍOS NÉSTOR; PANZERA FRANCISCO; LOBBIA PATRICIA A; SÁNCHEZ CASACCIA PAZ; ROJAS DE ARIAS ANTONIETA; CAVALLO MARÍA JOSÉ; GIGENA GISEL; CLAUDIA S RODRÍGUEZ; NATTERO JULIETA

PARASITES AND VECTORS

BIOMED CENTRAL LTD

Lugar: Londres; Año: 2024

1756-3305

Background: Triatoma garciabesi, a potential vector of Trypanosoma cruzi, is common in peridomestic and wild environments. It is distributed in northwestern and central Argentina, western Paraguay and the Bolivian Chaco. Genetic differentiation of a species across its range can help to understand dispersal patterns and connectivity between habitats. Dispersal by flight is considered the main active dispersal strategy used by triatomines. In particular, the morphological structure of hemelytra is associated with their function. The aim of this study was to understand how genetic diversity is structured, how morphological variation of dispersal-related traits varies with genetic diversity, and how the morphological characteristics of dispersal-related traits may explain the current distribution of genetic lineages in this species.Methods: Males from 24 populations across the distribution range were examined. Cytochrome C oxidase I gene (coI) was used for genetic diversity analyses. A geometric morphometric method based on landmarks was used for morpho-functional analysis of the hemelytra. Centroid size (CS) and shape of the forewing, and contour of both parts of the forewing, the head and the pronotum were characterised. Length and area of the forewing were measured to estimate the aspect ratio.Results: The morphometric and phylogenetic analysis has identified two distinct lineages, namely the Eastern and Western lineages, which coincide with different ecological regions. The Eastern lineage is found exclusively in the eastern region of Argentina (Chaco and Formosa provinces), whereas the Western lineage is prevalent in the rest of the geographical range of the species. CS, shape and aspect ratio of the hemelytra showed differences between lineages. The stiff portion of the forewing was more developed in the Eastern lineage. The shape of both portions of the hemelytra showed significant differences. Heads and pronota showed shape differences between lineages. Conclusions: The results provide preliminary insights into the evolution and diversification of T. garciabesi. Variation in forewing, pronotum and head is congruent with genetic divergence. Consistent with genetic divergence, morphometry variation was clustered according to lineages, with congruent variation in size and shape of the forewing, pronotum and head.