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Palms are ubiquitous across Neotropical landscapes, from pristine forests or savannahs to large cities. Although palms provide useful ecosystem services, they also offer suitable habitat for triatomines and for Trypanosoma cruzi mammalian hosts. Wild triatomines often invade houses by flying from nearby palms, potentially leading to new cases of human Chagas disease. Understanding and predicting triatomine-palm associations and palm infestation probabilities is important for enhancing Chagas disease prevention in areas where palm-associated vectors transmit T. cruzi. We present a comprehensive overview of palm infestation by triatomines in the Americas, combining a thorough reanalysis of our published and unpublished records with an in-depth review of the literature. We use site-occupancy modeling (SOM) to examine infestation in 3590 palms sampled with non-destructive methods, and standard statistics to describe and compare infestation in 2940 palms sampled by felling-and-dissection. Thirty-eight palm species (18 genera) have been reported to be infested by ∼39 triatomine species (10 genera) from the USA to Argentina. Overall infestation varied from 49.1-55.3% (SOM) to 62.6-66.1% (dissection), with important heterogeneities among sub-regions and particularly among palm species. Large palms with complex crowns (e.g., Attalea butyracea, Acrocomia aculeata) and some medium-crowned palms (e.g., Copernicia, Butia) are often infested; in slender, small-crowned palms (e.g., Euterpe) triatomines associate with vertebrate nests. Palm infestation tends to be higher in rural settings, but urban palms can also be infested. Most Rhodnius species are probably true palm specialists, whereas Psammolestes, Eratyrus, Cavernicola, Panstrongylus, Triatoma, Alberprosenia, and some Bolboderini seem to use palms opportunistically. Palms provide extensive habitat for enzootic T. cruzi cycles and a critical link between wild cycles and transmission to humans. Unless effective means to reduce contact between people and palm-living triatomines are devised, palms will contribute to maintaining long-term and widespread, albeit possibly low-intensity, transmission of human Chagas disease.

A summary is made of the results obtained from the study of the adsorption and interaction mechanisms of a series of organophosphorus pesticides (phosphates, phosphorothiolates, phosphorothionates and phosphorothiolothionates) with montmorillonite, with the aim of establishing relationships between the chemical structure of these compounds and the adsorption and interaction mechanisms with this clay. Many of the organophosphorus pesticides studied are adsorbed into the interlayer space of montmorillonite. The intercalation causes different degrees of expansion (different types of complexes) principally as a function of the chemical structure of the organic compound. The presence in the organic molecules of the P0 and PS groups and the size and composition (functional groups present) of the radicals are the two most important factors. Both the nature of interlayer cations and the previous hydration status of montmorillonite influence adsorption. In some cases the polarizing power of the interlayer cation is a conditioning factor of the degree of interlayer expansion, whereas in others the cation charge is responsible for this. Results of infrared spectroscopy show that interaction is of the dipole ion type and that it depends on the presence of the P0 or PS group in the molecule and also on the functional groups present in the side chains. These factors, together with the situation of these latter groups in the side chains, condition the arrangement adopted by the molecules of a pesticide in the interlayer space.