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Many species found in the Edwards Aquifer in Texas face several threats to their ecosystem, especially over pumping water, pollution, and competition from introduced species.

Two of these species include the Comal Springs dryopid beetle (Stygoparnus comalensis) and the Comal Springs riffle beetle (Heterelmis comalensis).

To help combat the threats to their ecosystem and increase their population, BIO-WEST, Inc. researcher Ely Kosnicki has been researching the life-histories of these two federally listed endangered invertebrates.

He recently published his research in the Journal of Insect Science. The goal of this study was to discover if there was a way to accurately determine the sex of living beetles without killing them or causing trauma to them, which increases the risk of death.

His overall research focuses on better understanding life-histories aspects of the Comal Springs dryopid beetle and the Comal Springs riffle beetle so that individuals can be bred in captivity.

“Both of these beetles represent unique species that have evolved specifically to the Comal Springs habitat and nearby habitats within the Edwards Aquifer,” Kosnicki said.

Some of these habitats can be found in and around residential areas such as back yards.

The Comal Springs dryopid beetle and the Comal Springs riffle beetle were declared endangered in 1997. Both beetles are protected by the United States Fish and Wildlife Service and the development of a self-propagating refuge population is important to stakeholders of the Edwards Aquifer.

By finding a reliable, non-lethal way to tell which beetles are male or female, researchers can conduct mating experiments to better understand how beetles from each species reproduce and grow into adults.

For example, females need to be tracked separately so the eggs produced by a single individual can be counted, Kosnicki said.

He is also interested in seeing if the individuals developing to adulthood in captivity are at a 1:1 sex ratio.

Since conducting this experiment, Kosnicki has recorded the first ever full rearing of the Comal Springs dryopid beetle from egg to adult in captivity.

He said he hopes to rear several more adults that he can use to develop a breeding program. This will create a population of beetles raised in captivity.

In the event of a disaster (natural or otherwise), these “refuge populations” can be used to replenish wild populations when favorable conditions return to their habitat.

Kosnicki is also working on enhancing the pupation rates of the Comal Springs riffle beetle.

“The current rearing program has a low rate of transformation of larvae into adults,” he said. “Having a better understanding of conditions that increase pupation rates will be a benefit to captive propagation efforts.”

Even though these aquatic beetles are small in size and have a small range of habitat, Kosnicki said these invertebrates still contribute to the planet’s biodiversity.

Biodiversity is important because it promotes ecosystem services that help sustain environmental health, he said, which in turn, promotes better human health.

A healthy planet – including all of the plants and animals living on it – is healthy for humans, he said.

To learn more about Kosnicki’s recent research, click here.