Opponents of a controversial construction project in Almonte, Ontario are pinning their final hopes on a rather unusual ally.

The tiny, and incredibly rare rapids clubtail dragonfly.

It’s hoped the endangered species will help put a halt to the expansion of the Enderdu Generating Station on the Mississippi River in the heart of Almonte. The habitat of any endangered species is automatically protected.

“They’re found in only four rivers in all of Ontario,” says Shaun McLaughlin, Mayor of the Muncipality of Mississippi Mills. “This is probably the best river for them. They’ve been found in three different spots in this river, most recently right here.”

The question is whether the dragonfly still exists in the area or not. Experts say there are likely only 20 to 30 on the river at most. And the adults only appear for 3 or 4 weeks a year in early to mid-summer.

In its environmental report, Enerdu says it didn’t find any clubtails.

Joachim Moenig is among those who disagree. Moenig lives on the river, near the dam project. He’s also a retired environmental biologist with the federal government. He says he’s seen clubtails nearby, and ye’s convinced the project is harming the local habitat. “The environmental assessment for this, I believe, was very deficient in my opinion,” says Moenig.

The Mayor says he has contacted the Federal Minister of the Environment and Climate Change, Catherine McKenna, with a request to intervene and halt construction of the dam. He is awaiting a response.

He also realizes that this is likely their last chance to stop the project, putting a lot of weight on some very tiny shoulders. “It’s not over until it’s over.”