No abstract

Bromeliad phytotelmata are frequently used by several Neotropical amphibian taxa, possibly due to their high humidity, microclimatic stability, and role as a refuge from predators. Indeed, the ability of phytotelmata to buffer against adverse environmental conditions may be instrumental in allowing some amphibian species to survive during periods of environmental change or to colonize sub-optimal habitats. Association between bromeliad traits and salamanders has not been studied at a fine scale, despite the intimate association of many salamander species with bromeliads. Here, we identify microhabitat characteristics of epiphytic bromeliads used by two species of the Bolitoglossa morio group (B. morio and B. pacaya) in forest disturbed by volcanic activity in Guatemala. Specifically, we measured multiple variables for bromeliads (height and position in tree, phytotelma water temperature and pH, canopy cover, phytotelma size, leaf size, and tree diameter at breast height), as well as salamander size. We employed a DNA barcoding approach to identify salamanders. We found that B. morio and B. pacaya occurred in microsympatry in bromeliads and that phytotelmata size and temperature of bromeliad microhabitat were the most important factors associated with the presence of salamanders. Moreover, phytotelmata with higher pH contained larger salamanders, suggesting that larger salamanders or aggregated individuals might modify pH. These results show that bromeliad selection is nonrandom with respect to microhabitat characteristics, and provide insight into the relationship between salamanders and this unique arboreal environment.

The chytrid fungus Batrachochytrium dendrobatidis (Bd) has been identified as a major threat to several amphibian populations in tropical forests. Amphibians that inhabit the phytotelmata (water tanks) of bromeliads may be especially at risk of Bd infection since the humid, environmentally buffered microhabitat that they prefer might also be favorable for Bd persistence on the host. To test this hypothesis, we sampled adults and tadpoles of the bromeligenous anuran Phyllodytes edelmoi (endemic to the northern Brazilian Atlantic Forest) from the bromeliad Portea leptantha for Bd, using qPCR. We also analyzed 8 bromeliad characteristics: water tank temperature and pH, canopy closure, tank diameter, number of leaves, bromeliad maximum column depth to store water, bromeliad relative volume, and season. Adult frogs preferentially selected bromeliads with a smaller diameter, more leaves and a relatively higher volume of water. We found that Bd was more prevalent in frogs inhabiting bromeliad phytotelmata with smaller diameters, suggesting that the behavioral preferences of P. edelmoi may be driving Bd infection patterns. Therefore, species such as P. edelmoi will be trapped by their own natural history traits. KEY WORDS: Pathogen · Batrachochytrium dendrobatidis · Phyllodytes · Atlantic Forest · BromeligenousResale or republication not permitted without written consent of the publisher