Contents lists available at ScienceDirect Acta Tropica journal homepage: www.elsevier.com/locate/actatropica How microclimatic variables and blood meal sources influence Rhodnius prolixus abundance and Trypanosoma cruzi infection in Attalea butyracea and Elaeis guineensis palms? Johan M. Calderón a, ⁎ , Diana Erazo b , Troy J. Kieran c , Nicole L. Gottdenker d , Cielo León a , Juan Cordovez b , Felipe Guhl a , Travis C. Glenn c , Camila González a a Centro de Investigaciones en Microbiología y Parasitología Tropical (CIMPAT), Departamento de Ciencias Biológicas, Universidad de los Andes, Bogotá D.C. 111711, Colombia b Grupo de Investigación en Biología Matemática y Computacional (BIOMAC), Departamento de Ingeniería Biomédica, Universidad de Los Andes, Bogotá D.C. 111711, Colombia c Department of Environmental Health Science, College of Public Health, University of Georgia, Athens, Georgia 30602, USA d Department of Veterinary Pathology, College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602, USA ARTICLE INFO Keywords: Chagas disease Triatomines Habitat selection Vector ecology Cleptohematophagy Disease ecology ABSTRACT Chagas disease is a zoonosis that affects several million people and is caused by the parasite Trypanosoma cruzi, which is mainly transmitted through the feces of triatomine bugs. Within triatomines, several Rhodnius species have been found inhabiting palms, and certain factors such as palm species and location have been related to the abundance and T. cruzi infection of those insects in palms. In this study, the main goal was to determine if R. prolixus abundances and infection rates in Attalea butyracea and Elaeis guineensis palms are related to ecological factors such as palm species, crown microclimate, and available blood meal sources. Triatomine sampling was performed in two municipalities of Casanare, Colombia, specifically in the intersection of riparian forests and oil palm plantations. For R. prolixus abundance per palm, the predictors showing more relationship were palm species and blood meal species identified in the palm, and for T. cruzi infection per triatomine, they were palm species and nymphal stage. Palm microclimate was very similar in both palm species and did not show a re- lationship with triatomine abundance. Comparing palm species, A. butyracea showed more blood meal species, including more refractory host species, than E. guineensis, but lower T. cruzi infection rate and parasitaemia. Interestingly, non-arboreal blood meal species were frequently found in the analyzed nymphs, indicating that the blood source for R. prolixus in palms corresponded to all the fauna located in the surrounded landscape and not only in the palm. These results could expose a new ecological scenario to interpret the T. cruzi transmission in sylvatic environments. 1. Introduction Several species of triatomine bugs are vectors of Trypanosoma cruzi, the etiological agent of Chagas disease. Along their distribution range, it has been shown that they have a close association with habitats that offer shelter and food (i.e. blood). In particular, several species of the genus Rhodnius are frequently found in palms (Abad-Franch et al., 2005; D'Alessandro et al., 1971; Dias et al., 2014; Justi et al., 2010; Ricardo-Silva et al., 2012; Romaña et al., 1999), since palm crowns appear to be suitable places for them to obtain shelter inside leaf axils and blood from the associated vertebrate fauna (Teixeira et al., 2001). Regarding public health, morphometric and molecular studies have demonstrated that Rhodnius triatomines migrate to households from the surrounding palms (Feliciangeli et al., 2007; Fitzpatrick et al., 2008; Gómez-Núñez, 1969). This could threaten vector control programs since houses previously treated with insecticide can be reinfested (Sanchez-Martin et al., 2006). Palm characteristics, such as crown microclimate, accumulated or- ganic matter, stem height, and associated-fauna, have shown a re- lationship with Rhodnius infestation and abundance in palms (Abad- Franch et al., 2015, 2010, 2005; Dias et al., 2011). Crown microclimate varies among palm species due to morphological differences (e.g. leaf https://doi.org/10.1016/j.actatropica.2020.105674 Received 13 May 2020; Received in revised form 18 August 2020; Accepted 19 August 2020 Abbreviations: GLMM, generalized linear mixed models; GLM, generalized linear models; PC, principal components; N1-5, nymphal stage 1 to 5 ⁎ Corresponding author. E-mail address: jm.calderon@uniandes.edu.co (J.M. Calderón). Acta Tropica 212 (2020) 105674 Available online 20 August 2020 0001-706X/ © 2020 Elsevier B.V. All rights reserved. T