Haliplus apostolicus is a Wisconsin Special Concern crawling water beetle that occurs near the shores of both still and running bodies of water such as ponds, lakes, streams, and slow-moving rivers. Documented in the central and northwestern parts of Wisconsin. Crawling water beetles (Haliplidae) are omnivorous and many species feed on both algae and small aquatic animals. The Haliplus genus is most frequently found in springs, ditches, and canals. Adults are 2.7-3mm long and appear almost completely black due to dark markings that cover the entire body.
