The Mole Salamander, One of Indiana’s most Recently Discovered Species

By Jim Horton

For a state with a long history of naturalist exploration, Indiana still manages to surprise the scientists who study its wildlife. One of the most striking examples came when researchers confirmed the presence of the mole salamander (Ambystoma talpoideum), a species never before recorded in Indiana.

The mole salamander is well known across the southeastern United States, with a range stretching from the Carolinas to Texas. Indiana, however, was never considered part of its distribution. That changed in 2004 when biologists from Purdue University surveyed a bald cypress swamp in Posey County and encountered a small but unmistakable population of the species.

The find was remarkable not only because the salamander had gone undetected for so long, but because the population sits far north of the species’ typical range. This makes it a disjunct population—a group living in isolation from the main body of the species.

The mole salamander is a stout bodied amphibian, ususally 3–5 inches long, with a broad head and a short, thick tail. Its coloration ranges from gray to brown, often sprinkled with subtle bluish flecks. The species gets its name from its behavior where they spends much of their lives underground or hidden beneath logs, leaf litter, and root systems.

The Indiana population was found in a bald cypress swamp, a habitat type more commonly associated with the Deep South than the Midwest. These wetlands offer suitable habitat for this species.

Because mole salamanders migrate to water only during the breeding season and spend the rest of the year hidden underground, it’s easy to see how they could remain undetected for decades.

Disjunct populations often represent remnants of ancient distributions—survivors from eras when climates and landscapes were dramatically different. Isolated populations can be vulnerable to habitat loss, wetland drainage, and climate shifts may threaten them more than their widespread counterparts.

Indiana is known for its salamander diversity; more than any other state, including the presence of rare unisexual salamander lineages. The mole salamander adds another layer to this ecological richness.

The discovery of the mole salamander in Indiana is a testament to the value of field research and the resilience of wildlife. Even in a state mapped, farmed, and studied for centuries, hidden species persist in quiet corners—waiting for the right moment, and the right observer, to be noticed.

The mole salamamders are listed as State Endangered in Indiana