Friday

Common Black Ground Beetle (Pterostichus melanarius)


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EFP-P1070675
(Fig. 01)
Picture Notes: On 08/09/2014 I was hiking near the Willow Springs Picnic Area inside Redrock Canyon when I looked down and found this large black, shiny beetle (Figs. 01 & 02). He was at least an inch long. I had the opportunity to observe him for scurrying around for several minutes. Whenever I confronted him with a twig to keep him contained, he would stop and point his head into the ground and raise his body into the air as if doing a headstand (Fig. 03).
                          
EFP-P1070676
(Fig. 02)
Description: This beetle is just one of many species which get the name "Common Black Ground Beetle." Although their body shapes and coloring vary somewhat, most are shiny black or metallic and have ridged wing covers (elytra). The elytra are fused in some species, particularly large Carabinae, rendering the beetles unable to fly. This ground beetle can grow up to three-quarters of an inch long. It is nearly all black with some dark reddish-brown coloring on antennae and legs. Many grooves run lengthwise down the beetle's wings.

They are usually searching for prey, which includes caterpillars, grubs, other species of beetles, fly maggots and pupae, aphids, weevils, earthworms, slugs, snails and other soft-bodied creatures. Predators of ground beetles are the same as those of other beetles, including toads, small snakes, shrews, and birds.
Common Black Ground Beetles breed in late Summer. The female lays eggs just below the soil surface. Larvae hatch and spend the Winter in the soil. In early Spring the larvae begin feeding and then turn into pupae (resting stage). They come out as adult beetles in the Summer.
                                 
EFP-P1070678
(Fig. 03)