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Chemical in paint appears to mimic pheromone to attract beetle

Below, Rosalia funebris, the banded alder beetle, explores the shoulder of Cornell entomologist E. Richard Hoebeke

Lana Preszler's beetle created quite a buzz. The Sacramento, Calif., area first-grader collected all the usual insects California kids can find in their backyards, but no other 7-year-old at Natoma Station Elementary School in Folsom, Calif., had Rosalia funebris. "This is the most pristine banded alder beetle I've seen," said E. Richard Hoebeke, assistant curator of Cornell University's insect collection. "It was fresh, newly emerged, not worn. It was a real nice specimen."

Hoebeke knows insects. With more than 200,000 species and 5 million specimens, the Cornell insect collection is among the world's top repositories. And thanks to Lana's keen eye, the collection just got better. This beetle is not commonly encountered, but when it arrives, it appears in numbers.

This story of a girl and her beetle begins with some off-white, acrylic exterior paint.

On May 18, Lana's father, Dennis Dahlquist, had just finished having the stucco exterior of his home painted. Late in the afternoon, Lana had noticed a big black and white insect climbing on the home's freshly painted exterior wall. It's a large, black, shiny insect, about 1 inch long, with white stripes daubed on its back, with antennae resembling the black-and-white striping on a coastal lighthouse.

Father and daughter captured it, put it in Lana's "bug farm" and took it to school for show-and-tell. The insect also caught the attention of the school's parents attending an evening open house. They were in awe.

But, no one knew what it was. To find out, the Dahlquists went to the Internet.

Firing up the Alta Vista search engine, Dahlquist keyed in the words, "black white insect." The search turned up many sites on the World Wide Web, including a Cornell news release and photo about the large black-and-white Asian longhorned beetle that has been decimating maple trees in Brooklyn, N.Y., and in Amityville, N.Y., on Long Island. [Please see web site:http://www.news.cornell.edu/Chronicles/9.19.96/Brooklyn_beetle.html].

Dahlquist couldn't help noticing that Lana's beetle looked eerily similar. So he sent an e-mail to Hoebeke at Cornell the next day. Hoebeke asked to see the specimen immediately and explained how to ship the beetle. The beetle made a cross-country journey.

"The Asian longhorned beetle has certainly raised a lot of attention. This shows that people are paying attention to the longhorns," Hoebeke said. The beetle arrived alive but Hoebeke quickly recognized that it was not the Asian longhorned beetle. Instead, it was the banded alder beetle, a docile, mild-mannered insect, content on living in dead or dying trees and native to western North America. It poses no harm to healthy trees.

Of all things, banded alder beetles are drawn to fresh paint.

Both sexes of the banded alder beetle were attracted to a Ukiah, Calif., paint shop and a prefabricated building in Santa Rosa, Calif., where the beetles were found drowned in paint, according to E. Gorton Linsley, at the University of California-Berkeley's entomology department. His scientific note of this beetle appeared in a 1995 issue of the journal Pan-Pacific Entomologist.

Linsley speculates that a volatile chemical in paint mimics a specific attracting pheromone, which draws the beetles to each other. If it were a naturally occurring host attractant, then other insects would be drawn to it. As of now, only the banded alder beetle is attracted.

"The banded alder beetle is scientifically interesting on its own merit," Hoebeke said.

The Cornell insect collection had a few of these beetles, but none as good as Lana's. So, by way of e-mail, the veteran entomologist asked the first-grader if he could keep it.

Lana's reply: "My whole class was in love with it. When [they saw it], they left with their mouths hanging open. We found two more this afternoon. You are welcome to keep the other one. I hope the people who see it will like it. Thank you, Lana." In a postscript, she asked where it will stay, what she should do with the other beetles and if it bites.

Hoebeke answered -- in Cornell's entomology department in Ithaca, N.Y.; to possibly keep a specimen but also to donate extra specimens to the University of California-Davis and the University of California-Berkeley; no, it doesn't bite -- and thanked her for Cornell's most recent acquisition.

And that's how a notable specimen of Rosalia funebris, the banded alder beetle, now occupies drawer 20 of the Cerambycinae (subfamily) and Cerambycidae (family) cabinets in Cornell's insect collection. The tag identifying it has Lana's name on it.

You can look it up.