Acknowledgments We are thankful to Dr. Mark Wilkinson (Natural History Museum, London) for helping us with the text of this note and to James P. Lewis (Froglog) for inviting us to write this note. We are in debt with Piktor Benmaman and Ricardo Alves da Silva for allowing us to use their pictures of Aparasphenodon brunoi and Scinax littoreus respectively.
in its diet (Silva et al, 1989; Silva & Britto-Pereira, 2009), and Scinax littoreus (Figure 5) that belongs to a group specialized in reproducing in bromeliads (Alves-Silva & Silva, 2009). Our study of the frogs in the Restinga de Maricá, State of Rio de Janeiro, published at Biotropica (Silva et al., 2011), was designed to answer some basic questions regarding the use of the most abundant bromeliad, Neoregelia cruenta (Figure 6), by frogs. We aimed to (1) describe how many frog species in the area used these plants, (2) if bromeliads were used differently by different species of frogs, and (3) if some of the physical characteristics of the bromeliads were somehow selected by the species of frogs when searching for a place to hide. Based on our findings we discuss and reinforce the need to conserve bromeliads as microhabitats for frogs.
Figure 4. Female Xenohyla truncata (Hylidae)
Our results confirm a morphological Figure 5. Scinax littoreus (Hylidae) plasticity trend in which bromeliads exposed directly to the sun are different from those that grow in the shade, protected from direct sun light by the covering of other plants in the interior of scrubs (Cogliatti-Carvalho & Rocha, 1999). Bromeliads that grew exposed to direct sun light are bulkier, shorter, have narrower and lighter green leaves and their thorns are stronger and more spaced. Bromeliads that grew on the shade have longer, darker green leaves, and less water Figure 6. Neoregelia cruenta (Bromeliacea) storage capabilities. It is also reported that, as a result of having oxygen levels are proved to be higher and a higher degree of deposition of organic ammonia and dissolved organic carbon debris inside their tanks, bromeliads lower (Guimarães-Souza et al., 2006). growing in shaded areas, within the Therefore we hypothesize that frogs scrubs, have a different and possibly less choose among bromeliads based on the hospitable water storage to anurans than quality of their stored water, rather than those directly in the sun. The chemistry their morphology, which may be harder of the water stored is significantly for a frog to detect. Considering the high different (Guimarães-Souza et al., 2006), frequency of bromeliads used by anurans which may affect the physiology of the during the whole year, our data reinforce anurans, including their respiration, and the importance of protecting these plants. influence the process of plant selection for We demonstrate the importance of sheltering. bromeliads as biodiversity amplifiers for anurans and the importance of these plants We discovered that frogs are more for their conservation. common in bromeliads growing exposed to direct sunlight, where dissolved 46 | FrogLog Vol. 97 | July 2011
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