"Tails" from the trail: The Appalachian Mountains' own butterfly

Happy summer solstice and Wildlife Wednesday! The end of spring beckons the sun to stick around for a bit longer today. Lengthy, warm days mean that many insects will be spreading their wings to grace the summer skies.

One insect that is finishing up its flight period with the switch into summer is the Appalachian Tiger Swallowtail. Yes, you heard it here, there is a butterfly that exclusively calls the Appalachian Mountain range its home!

These butterflies are quite a recent discovery, only being confirmed as an official species in 2002 (Paluvaan & Wright 2002). They tend to inhabit the mid- to high-elevation areas of the Appalachians from Georgia to Pennsylvania. Also in their range is the Eastern Tiger Swallowtail, and in the northern range, is the Canadian Tiger Swallowtail. After genomic analysis, the Appalachian Tiger Swallowtail was found to be a hybrid of these other two species.

From left to right: Appalachian Tiger Swallowtail (credit: @sharkfanboy), Eastern Tiger swallowtail (credit: Benji Beluga), and Canadian Tiger Swallowtail (credit: Chris Fisher)

From the Eastern Tiger Swallowtail, the hybrids inherited the traits of sexual dimorphism and mimicry (Kunte et al. 2011). But hold on- what do these “traits” even mean? Well, sexual dimorphism is when there are differences in traits between males and females of a species- such as color or size. A common example of this in the animal kingdom is cardinals. In both the Appalachian and Eastern Tiger Swallowtails, the males are yellow, and the females can be yellow or black. The difference in color can be accounted for by mimicry- or appearing as another species. The females are mimicking the Pipevine Swallowtail, which is poisonous to predators.

The Appalachian Tiger Swallowtail shares with the Canadian Tiger Swallowtail its preference for colder climates, which gives it the unique Appalachian Mountain habitat. Additionally, these two species only have one brood per season- which means they have one reproductive event per season (Kunte et al. 2011). This reproductive strategy is linked to shorter, cooler summer seasons in montane and higher latitude environments.

The hybrid has only been seen laying its eggs on wild black cherry (Prunus serotina). However, for nectaring it enjoys a host of mountain plants including azaleas, mountain laurels, honeysuckle, blackberry, and multiflora rose.

From left to right: wild black cherry (credit: @evangrimes), mountain laurels (credit: @lukentn), and pink azalea (credit: @wilson59604)

If you’re trying to convince your friends to hike the AT or even just a portion of it, you can entice them with the fact that the trail has its own butterfly!

Works cited and further reading:

https://www.butterfliesandmoths.org/species/Papilio-appalachiensis

https://www.butterfliesandmoths.org/species/Papilio-glaucus

https://www.butterfliesandmoths.org/species/Papilio-canadensis

Kunte K, Shea C, Aardema ML, Scriber JM, Juenger TE, et al. (2011) Sex Chromosome Mosaicism and Hybrid Speciation among Tiger Swallowtail Butterflies. PLOS Genetics 7(9): e1002274. https://doi.org/10.1371/journal.pgen.1002274

Taxonomic Report of the International Lepidoptera Survey (June 15, 2002) 3(7): 1-20

Posted on June 21, 2023 09:17 PM by hai827