### Identification The Black Carpet Beetle (*Attagenus unicolor*) is a master of understated camouflage. Measuring a modest 3–5 mm, adults possess a distinctively elongated, oval body—more bullet-shaped than the rounder *Anthrenus* species. They are uniformly matte black or dark chocolate brown, lacking the mottled scales of their cousins. Look closely with a hand lens: you’ll see the surface is finely punctured and covered in short, stiff hairs. Their legs and antennae often transition into a reddish-brown hue. Distinguish them from the Common Carpet Beetle by their solid coloring and the lack of orange-red scales along the midline.
### Habitat & Range This cosmopolitan beetle is truly global, thriving wherever humans—or birds—reside. In the wild, they are frequent inhabitants of bird and rodent nests, scavenging in the debris. In urban environments, they gravitate toward dark, undisturbed corners: under baseboards, within wall voids, or inside air ducts. They are found from sea level to high elevations, provided there is a source of organic protein.
### Behaviour You will encounter two very different "personalities" depending on the life stage. Adults are phototactic (attracted to light); you’ll often spot them on windowsills in the spring, desperate to head outdoors to mate. Conversely, the larvae are lucifugous (light-shunning). These "carrot-shaped" larvae are golden-brown with a signature tuft of long bristles at the tail. They move with a slow, wandering gait, grazing through dark crevices. If disturbed, the larvae often "play dead," curling slightly to protect their undersides.
### Diet The life of *A. unicolor* is a tale of two diets. The adults are gentle nectar-feeders, frequenting Spiraea and wild buckwheat to fuel their flight. However, the larvae are specialized scavengers of the high-protein world. They possess rare enzymes to break down keratin, feeding on wool, silk, feathers, hair, and even dried insect collections. They are the "clean-up crew" of the natural world, recycling tough animal proteins that other insects cannot digest.
### Fascinating Fact The larvae of the Black Carpet Beetle are the ultimate survivalists; if food is scarce, they can undergo "retrogressive molting." Instead of growing larger, they actually shrink in size with each molt, effectively "growing backward" to lower their metabolic needs until they find their next meal!