The food animals eat and the way they obtain that food are central in species ecology (Curio, 1976; Slip and Shine, 1988). Feeding habits of snakes are of particular interest because they show remarkable adaptations for locating, capturing, subduing, and ingesting a wide array of prey (Cundall and Greene, 2000). Snakes’ diets vary within and between taxa due to evolutionary history, ontogeny, as well as differences in prey size, prey type, aspects of foraging, and microhabitat use (Greene, 1997; Cundall and Greene, 2000; Alencar et al., 2013). Detailed knowledge on feeding ecology and behaviour of several species is poorly understood, especially for neotropical species (e.g., Marques and Sazima, 1997; Alencar et al., 2013). Most of the data available about feeding behaviour of snakes comes from single observation (e.g., Rojas-Morales et al., 2017; Guedes et al., 2018a; Mario-da-Rosa et al., 2020), captivity (e.g., Braz et al., 2006; Rojas-Morales, 2013), or by encounters in the wild (e.g., Sazima, 1974, 1989; Gómez-Hoyos et al., 2015). Among neotropical arboreal snakes, species in general such as Imantodes Duméril, 1853 and Sibon Fitzinger, 1826 show a compressed body, disproportionately slender neck, big and movable eyes, and a blunt head, making them easy to distinguish from other sympatric snakes. Other than their morphological similarity, arboreal niche, and nocturnal activity pattern (Ray, 2012), these groups have a substantially different diet. Imantodes prey mainly upon Anolis lizards (Duellman, 1978; Martins and Oliveira, 1998; Savage, 2002; Sousa et al., 2014), with frogs and amphibian eggs also recorded (Zug et al., 1979; Martins and Oliveira, 1998). In contrast, Sibon are included among the so- called “goo-eaters” (Cundall and Greene, 2000; Savage, 2002; Zaher et al., 2014), which exhibit a feeding strategy based on the consumption of small, soft-bodied invertebrates, including slugs and land snails. Goo- eaters have a specialized dentition and glandular toxins secreted by the infralabial glands to extract snails from their shells (Sheehy, 2013; Zaher et al., 2014). Sibon may also feed on annelids and amphibian eggs (Ray et al., 2012; Ward, 2016). Imantodes cenchoa (Linnaeus, 1758) and Sibon nebulatus (Linnaeus, 1758) share a similar geographical distribution, ranging from southeastern Mexico across Central America into northern South America (Guedes et al., 2018b), inhabiting primary and second-growth forests, shrubs, and crops from sea level to 2300 m in elevation (Myers, 1982; Savage, 2002; Solórzano, 2004; Rojas-Morales et al., 2014, Missassi and Prudente, 2015). Both species are commonly syntopic in forested habitats in Colombia at elevations below 1500 m, where they are also usually one of the most frequently Herpetology Notes, volume 14: 717-723 (2021) (published online on 21 April 2021) On delicate night hunters: observations of the feeding behaviour of Imantodes cenchoa (Linnaeus, 1758) and Sibon nebulatus (Linnaeus, 1758) through staged and natural encounters (Serpentes: Dipsadidae: Dipsadinae) Julián A. Rojas-Morales 1,2 , Juana Valentina González 2 , Juan Camilo Cepeda-Duque 3 , Mateo Marín-Martínez 4 , Román Felipe Díaz-Ayala 4 , and Thaís B. Guedes 5,* 1 Grupo de Investigación en Genética, Biodiversidad y Manejo de Ecosistemas, Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales Universidad de Caldas, Caldas 170004, Colombia. 2 Grupo de Investigación en Biología de la Conservación y Biotecnología, Corporación Universitaria de Santa Rosa de Cabal, Santa Rosa de Cabal, Risaralda 661027, Colombia. 3 Laboratorio de Ecología de Bosques Tropicales y Primatología, Departamento de Ciencias Biológicas, Universidad de Los Andes, Bogotá, D.C. 11711, Colombia. 4 Grupo de Ecología y Diversidad de Anfbios y Reptiles, Universidad de Caldas, Manizales, Caldas 170004, Colombia. 5 Centro de Estudos Superiores de Caxias, Universidade Estadual do Maranhão, Caxias, Maranhão, 65064-380, Brazil; and Gothenburg Global Biodiversity Center, University of Gothenburg, Department of Biological and Environmental Sciences, Box 461, 40530 Göteborg, Sweden. * Corresponding author. E-mail: thaisbguedes@yahoo.com.br © 2021 by Herpetology Notes. Open Access by CC BY-NC-ND 4.0.