Guatemalan beaded lizards (Helodermatidae: Heloderma charlesbogerti) navigate and follow a scent trail in maze tasks.

Abstract

Maze studies have provided substantial information about nonhuman cognition, such as insights on navigational strategies, spatial memory, and choice discriminations. This knowledge can aid in how we understand the foraging strategies of many animals, particularly understudied and endangered species, such as the Guatemalan beaded lizard (Heloderma charlesbogerti). These actively foraging lizards rely on chemoreception to locate prey, but it is unknown to what extent they engage in olfaction and vomerolfaction to hunt and navigate their environment. We investigated how Guatemalan beaded lizards moved through a physical maze. When navigating an eight-arm radial maze with all arms baited, lizards tended to turn into the immediately adjacent arm in a single direction, similar to other reptiles that have been tested in radial arm mazes. In a T-maze, the lizards had to discriminate between arms that contained scent and no-scent from a distance. They were generally unable to choose the baited (correct) arm at levels greater than chance, indicating an inability for this discrimination. With the addition of a scent trail, however, all lizards chose the baited arm at levels significantly above chance, and this increased accuracy was correlated with increased latency to make the arm choice. The lizards also demonstrated a decreased rate of tongue flicking as proximity to reward increased. Guatemalan beaded lizards can efficiently navigate a radial arm maze and can successfully use vomerolfaction with substrate-borne cues to locate prey, but they appear to have minimal olfaction abilities when sensing from a distance. (PsycInfo Database Record (c) 2024 APA, all rights reserved).