Ecological Interactions and Environmental Stress Indicators Observed in the Family Zamiaceae at the Botanical Garden of the National Autonomous University of Honduras

Abstract

In the cycad collection of the Botanical Garden of the National Autonomous University of Honduras (UNAH), 56 individuals belonging to 7 cycad species were recorded (5 of them endemic to Honduras), distributed across three genera: Dioon (Dioon mejiae), Ceratozamia (Ceratozamia hondurensis), and Zamia (Zamia furfuracea, Zamia onan-reyesii, Zamia oreillyi, Zamia sandovalii, and Zamia standleyi). Zamia onan-reyesii exhibited the highest number of interactions with invertebrates (68.8%), particularly herbivory by butterfly larvae, whereas Zamia sandovalii presented interactions without a clear pattern. Most interactions involved saprophagous insects such as Curculionidae and Labiduridae, attracted by decomposing strobilus remains. Mechanical stress caused by falling branches of Enterolobium cyclocarpum, along with light competition from certain invasive species, limits the growth of the cycads. In addition, Ceratozamia hondurensis and some strobili exhibit morphological deformities; species such as Zamia onan-reyesii show symptoms of chlorosis due to nutrient deficiency, and Dioon mejiae displays signs of fungal infection. The objective of this research was to observe, describe, and analyze the ecological interactions and signs of environmental stress present in species of the family Zamiaceae at the Botanical Garden of the National Autonomous University of Honduras, to understand the factors influencing their health status and conservation.