Our insect of the week for December 22, 2025 is Hydrophilus ovatus [COLEOPTRA: Hydrophilidae]. This species was described by Max Gemminger (a German entomologist) & Edgar von Harold (another German entomologist) in 1868. Max was curator at the Royal Bavarian Museum in Munich and worked with Edgar to produce a 12 volume catalog of beetles. The first part of the catalog was published in 1868 and finally completed in 1876.

This species of water scavenger beetle is native to most of the eastern United States (including all of central Illinois). Adults are often attracted to lights at night. Larvae are aquatic predators. Most are found in shallow parts of ponds as the larvae need oxygen.

The adult shown here was collected by Mark DuBois in Peoria County, Illinois.