The Taxonomy and Population Structure of the Buckeye Butterflies (GenusJunonia, Nymphalidae: Nymphalini) of Florida, USA

Abstract

The buckeye butterflies (genus Junonia) that occur in Florida, USA have been an ongoing taxonomic challenge for over 100 years. Schwartz (1987. Milwaukee Pub. Mus. Contrib. Biol. Geol. 73: 21) described the situation succinctly: “No other lepidopteran on the Florida Keys nor in south Florida, presents the taxonomic problems as Junonia.” The current consensus recognizes 3 different forms of Junonia in Florida based on morphological characters, but there is a general lack of consensus regarding the appropriate scientific names for each form. Similarities between the species that occur in Florida, intraspecific variation, and possible hybridization between species have often made it challenging to identify specimens, define the population structure of Junonia butterflies, or to understand the relationships of these butterfly populations to those elsewhere in the New World. We use a combination of morphological characters, mitochondrial cytochrome oxidase I barcodes, nuclear wingless DNA sequences, and randomly amplified DNA fingerprints from Junonia from Florida, the Caribbean, and North and South America to resolve issues of taxonomy and population structure in this genus. We conclude that the common buckeye (J. coenia), the mangrove buckeye (J. neildi), and the tropical buckeye (J. zonalis) occur in Florida and that hybridization between these species takes place in this region.