Crawling Water Beetle?

These little beetles have been puzzling me for a long time, as with their distinct heads, they don't look like Predacious Diving Beetles. My field guide to aquatic invertebrates in Kansas suggests that these little guys, with the two dark spots behind the head, could be Crawling Water Beetles (Haliplidae), Genus Peltodytes. Help with confirming or denying the ID and learning more about these fellows would be appreciated!