The banded alder borer, Rosalia funebris, is a member of the very diverse family of longhorn beetle

Longhorn beetle

The longhorn beetles are a cosmopolitan family of beetles, typically characterized by extremely long antennae, which are often as long as or longer than the beetle's body...

s.

Appearance

Like many others in the family Cerambycidae, R. funebris has strikingly colored wing covers (elytra). The elytra are dark with three white bands. The thorax (pronotum) is white with a large black spot. The alder borer's antennae

Antenna (biology)

Antennae in biology have historically been paired appendages used for sensing in arthropods. More recently, the term has also been applied to cilium structures present in most cell types of eukaryotes....

 are banded white and black. The male's antennae are longer than his body, but the female's are shorter. Long and narrow, the body of R. funebris may grow to be 38 millimetres (1.5 in).

Distribution

Located along western North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

, Alaska

Alaska

Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

 through California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

, and in New Mexico

New Mexico

New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...

, the banded alder borer may be found in the spring and summer on the bark of alder trees.

The exact reason (pheromone?) is unknown, but R. funebris is drawn to recently painted buildings and may be found, in multitudes, resting on the paint.

Larvae

The adult wood-boring beetles lay their eggs in a crevice of the bark on hardwood trees such as Oregon ash

Oregon Ash

Fraxinus latifolia is a member of the ash genus Fraxinus, native to western North America.-Distribution:Fraxinus latifolia is found: on the west side of the Cascade Range from southwestern British Columbia south through western Washington, western Oregon, and northwestern California; and in...

, New Mexico willow, and California laurel/Oregon myrtle. From there the larvae

Larvae

In Roman mythology, lemures were shades or spirits of the restless or malignant dead, and are probably cognate with an extended sense of larvae as disturbing or frightening...

 bore into the wood. Unlike the oval (in cross-section) tunnels of the Buprestidae larva, larval Cerambycidae tunnels are circular (in cross-section) and will generally go straight for short distances between turns.

Food

Most mature Cermabycidae feed on flowers. The larvae consume wood. The species generally prefers downed trees, instead of living trees, so the alder borer is not considered a pest

Sound

When handled or threatened R. funebris makes an audible noise similar to that of a squeaky running shoe.

Other Rosalia species

• Rosalia alpina (Linnaeus, 1758) – Rosalia longicorn
• Rosalia batesi Harold, 1877
• Rosalia coelestis Semenov, 1911
• Rosalia houlberti Vuillet, 1911
• Rosalia lameerei Brogn, 1890