Hungerford's Crawling Water Beetle (Brychius hungerfordi)


Life History


From a size standpoint, the Hungerford's crawling water beetle would be a contender for the smallest of Michigan endangered or threatened animals. At a mere 1/4 inch in size, it is difficult to notice even when you are searching for them. Known from only two sites in northern Michigan, and one in Ontario, this tiny aquatic beetle is one of Michigan's rarest species. The species is a post-glacial relict requiring cold, clear streams for its existence.

The wing covers of this yellowish brown beetle are marked with irregular dark markings. The larvae are light yellow-brown with hooked tails.


Hungerford's Crawling Water BeetleHungerford's crawling water beetles prefer cool water (15-20 degrees C), well-aerated streams with a sand, gravel, cobble bottom. Historically, beaver dams may have been an important component of the beetle's environment. The backwater of dams stabilizes water levels, and the downstream sides often provides riffle areas preferred by the beetle.



Little is know about the ecology of the Hungerford's crawling water beetle, but is assumed that they trap air bubbles beneath their wing covers similar to other relatives of this beetle. Both adult and larvae are herbivorous feeding on algae growing on the bottom. The larvae's specialized hook tail makes this beetle especially adapted to feeding in swift riffle currents.

Preservation of this species will require protection of existing sites with additional research into the life cycle and feeding habitats of this species. Once this information is determined, the next step may be the transplant of populations into suitable habitat to provide additional protection to the beetles.


Non-DNR Links

Species Profile (U.S. Fish & Wildlife Service)

Brychius hungerfordi (University of Michigan, Museum of Zoology)