First Observations of Butterfly (Pedaliodes: Satyrinae: Nymphalidae) Visits to a Wild Anthurium (Araceae)

 

Robert Bleiweiss, Angelica Sofia Nogales Trujillo, Thomas B. Croat, Cesar Garzon Santomaro

 

ABSTRACT

Aroids are visited by a diverse assortment of animals, including many arthropods and some birds. It is therefore surprising that reports of butterflies visiting aroids are limited to plants grown in Botanical Gardens or in cultivation. Thus, the role of butterflies in the biology of wild aroids remains unclear. Observations at Anthurium bustamanteae (Croat et al. 2020), a species recently discovered at 2700 m in upper montane cloud forests on the eastern slope of the Andes in northern Ecuador, advanced understanding of butterfly-aroid associations in several important respects. Over approximately five weeks, two species of Pedaliodes (Satyrinae, Nymphalidae) repeatedly visited both female-phase and male-phase inflorescences under a variety of weather conditions. The butterflies were observed to pick up pollen and feed at fluid secretions with their proboscises while they perched along male-phase spadices. One or both Pedaliodes species also formed apparent feeding queues of up to three individuals seeking to access a fluid-rich zone on the male-phase spadix. More direct interference competition over the surface of the spadix was expressed as aggressive dominance over butterflies by a wasp, which actively chased butterflies around the spadix. Evidence that Pedaliodes visit aroids even when they experience costs (weather, aggression, competition) and benefits (potentially nutritious aroid secretions) of exploiting aroids in the wild suggests a dependable ecological relationship. These data confirm an earlier report that butterflies are poised to provide pollination services to aroids, and that nymphalid butterflies in particular may have a special ecological relationship with Araceae, including Anthurium.

 

KEYWORDS

Ecuador, Montane, Cloud Forest, Mutualism, Pollination, Red Coloration, Spadix, Wasp