A unique story of parallel evolution in moths unraveled

Washington, Sept 2 (ANI): A new revision of the taxonomic relationships among one group of moths, the subfamily Dioptinae, sheds light on the diversity of tropical moth species and presents a unique story of parallel evolution.

"These diurnal moths are a microcosm of butterfly evolution," said James Miller, author of the new Bulletin of the American Museum of Natural History and a research associate in the Division of Invertebrate Zoology at the Museum.

"There are about 500 spectacular dioptine species, all of which evolved from a common ancestor-a nondescript brown nocturnal moth-into a diversity of butterfly mimics," he added.

Miller qualifies this with a technicality, though, noting that no one is sure whether butterflies or diurnal moths evolved their colors first (and who is really mimicking whom).

The wing pattern diversity within the subfamily is enormous: some species mimic clear-winged butterflies and inhabit the darker parts of the forest understory where their co-mimics fly.

Still others have wings that are colored blue and yellow and feed on melastomes.

About 100 species feed on Passiflora, the poisonous passion flowers famous for being consumed by the caterpillars of Heliconious butterflies.

In fact, although most of the Dioptinae are diurnal, or fly during the day, a few species like those in Xenomigia have re-conquered the night.

Although most dioptines are neotropical, ranging from lowland jungles to cloud forests at 4,000 meters in the Andes, Phryganidia californica occurs in the western United States.

Miller's new revision of the Dioptinae is the first systematic look at this group in almost a century.

After studying over 16,700 specimens housed at 38 different institutions and private collections around the world, Miller discovered and described 64 new species and seven new genera, bringing the total to 456 species in 43 genera.

Some of the new species were found during field work in parts of the tropical Americas poorly explored by lepidopterists.

Even so, there is much more work to be done on the Dioptinae.

Miller estimates that there are about 100 to 150 species in collections that still need to be described and inserted into the taxonomy, and he thinks that additional fieldwork in under-sampled countries like Bolivia and Colombia will ultimately bring the total number of species to between 700 and 800.

Miller's careful analysis has dissected the taxonomic groups, finding that 47 of the previously named species could be included within another existing species. (ANI)