Yellow-Bellied Kingsnake is Actually Three Separate Species

Link with figures: http://www.sci-news.com/biology/yell...ies-04265.html


According to a new study published in the journal Molecular Phylogenetics and Evolution, the yellow-bellied kingsnake (Lampropeltis calligaster), a snake found across a large swath of the eastern U.S., is actually three separate species rather than just one.

The yellow-bellied kingsnake, also known as the prairie kingsnake, is a non-venomous species of snake endemic to the U.S. Its range extends from northern Florida to southern Texas, and north to Nebraska, Illinois, Kentucky, and Maryland.

The species is light brown or grey in color, with brown or reddish brown blotches that have dark borders. Adults reach lengths of 24-42 inches (61-106.7 cm).

The yellow-bellied kingsnake is found in various habitats, including weedy fields, farmland, barnyards, pastures, prairies, rocky hillsides, thickets, open woodland, sandhills, pine flatwoods, landward side of barrier beaches, coastal salt-grass savannas, marsh borders, and residential areas.

This secretive snake, especially females, spends much time underground or under surface cover. Eggs are laid in an underground cavity.

There are three subspecies of the yellow-bellied kingsnake, two of which started as distinct species when they were first discovered and then demoted after more study.

But the new study, by Dr. Frank Burbrink from the American Museum of Natural History and Dr. Alexander McKelvy from the City University of New York’s College of Staten Island, elevates them back to individual species with specific habitats: the prairie kingsnake (Lampropeltis calligaster) in the prairies west of the Mississippi River, the mole kingsnake (Lampropeltis rhombomaculata) in the forests east of the Mississippi, and the South Florida mole kingsnake (Lampropeltis occipitolineata) in South Florida wet prairies.


“Not only have we uncovered multiple species, but we’re making steps toward understanding the mechanisms that are generating biodiversity in the U.S.,” Dr. Burbrink said.

The results of the study also indicate that diversification of the yellow-bellied kingsnake — and possibly of many other vertebrates living on both sides of the Mississippi River — is influenced not by the river itself, as predominately thought, but by the different ecological environments on each side.

“We found three species inhabiting distinct ecological niches with divergences dating to the mid- and early-Pleistocene with subsequently stable or increasing effective population sizes, further supporting the idea that the Pleistocene was an important driver of diversification in North America,” the authors said.

“Our results lead to a revised hypothesis that ecological divergence has occurred in this group across environments associated with the Mississippi River and at the Florida peninsula.”

“Importantly, in their western distributions, we show that species divergence is associated with the ecological transition from distinct forested habitats to grasslands, rather than the nearby Mississippi River, a barrier often implicated for many other organisms.”

The findings are vital to conservation efforts because where there was once a very large population of a single wide-ranging species, there are now three species with considerably smaller numbers.

The researchers point out that the South Florida mole kingsnake is particularly at risk, and has plenty of company. Urbanization of the Florida landscape since 1960 has been faster than anywhere else in the U.S., with human population doubling every 20 years.

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A.D. McKelvy & F.T. Burbrink. 2017. Ecological divergence in the yellow-bellied kingsnake (Lampropeltis calligaster) at two North American biodiversity hotspots. Molecular Phylogenetics and Evolution 106: 61-72; doi: 10.1016/j.ympev.2016.09.006