Meet the Beetles, Part 1 – Bess Beetle and Stag Beetle

Let’s begin by learning to differentiate a couple of beetles that look somewhat similar: Bess Beetle (Odontotaenius disjunctus); and Reddish-brown Stag Beetle (Lucanus capreolus).

Bess Beetle (Odontotaenius disjunctus)

Bess Beetles are big and glossy black. Their exoskeleton reminds me of patent leather shoes. At 30-40 mm in length (~1.0-1.5 inches), Bess Beetles are one of the larger beetles commonly seen in forested parks such as Huntley Meadows Park.

15 MAY 2015 | HMP | Bess Beetle

Bess Beetles live inside rotting logs in forests, although I have see them quite often crossing the gravel trail that goes through the forest at Huntley Meadows.

15 MAY 2015 | HMP | Bess Beetle

Notice the Bess Beetle has a striated, or grooved abdomen; Reddish-brown Stag Beetle has a smooth abdomen.

15 MAY 2015 | HMP | Bess Beetle

Reddish-brown Stag Beetle (Lucanus capreolus)

Reddish-brown Stag Beetles are, well, reddish-brown, and at 20-36 mm sans mandibles (~0.7-1.4), almost as big as Bess Beetles.

17 JUL 2015 | HMP | Reddish-brown Stag Beetle (female)

This individual is a female, as indicated by the size of its mandibles. Females have smaller mandibles than males.

“Males use [their larger] mandibles to fight at breeding sites.” Source Credit: Species Lucanus capreolus – Reddish-brown Stag Beetle.

17 JUL 2015 | HMP | Reddish-brown Stag Beetle (female)

Adult stag beetles feed on tree sap; larvae feed on rotting logs. This individual was spotted near a large, man-made brush pile.

Related Resource: Meet the Beetles, Part 2

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