Imposing order. A recently discovered specimen from Africa (top) and an amber-encased fossil from Europe (bottom) indicate the new order's wide distribution.

Branch Added to Insect Tree

Liz is a staff writer for Science.

A graduate student has made the find of a lifetime: a new insect order. The last time the insect kingdom gained a new order was almost a century ago, and the new discovery "is an extraordinary event," says Harvard entomologist Edward O. Wilson.

In June 2001, Oliver Zompro, a graduate student interested in stick insects at the Max Planck Institute for Limnology in Plön, Germany, was visiting London's Natural History Museum. A curator showed him a baffling male insect that had been a mystery since it was collected in Tanzania in 1950. Just weeks later, an amber collector sent Zompro a similar-looking amber-encased fossil, and Zompro began to suspect that he had come across a new order. Soon he came across a third specimen, a female from Namibia, warehoused at the Berlin Natural History Museum since 1909.

Seeking help, Zompro turned to colleagues at the Zoological Museum of the University of Copenhagen. Niels Peder Kristensen and Klaus-Dieter Klass found that all three specimens shared some characteristics with stick insects and an obscure group called ice crawlers. But Klass observed that the female lacked the plate on the underside of its abdomen that covers egg-laying appendages in stick insects. Stick insects also have elongated thoraxes, with a stretched-out middle segment. In the new specimens, the segments are each about the same size. Furthermore, Klass discovered that the female's stomach was full of insect parts; stick insects are vegetarians, not carnivores.

The researchers therefore argue that the three new species together make up a separate order, which they have named Mantophasmatodea, for its superficial resemblance to the praying mantis and phasmids, the stick insects. "I am glad this group has a name and a place," says paleoentomologist George Poinar of Oregon State University in Corvallis. Until now, he says, "anyone who looked at them really couldn't put them anywhere."

The new order may soon have more members. Zompro and Eugene Marais of the National Museum of Namibia in Windhoek have just discovered two more Mantophasmatodea species in Namibia, says Kristensen, and living specimens have been brought to Zompro's lab for behavioral studies. All these finds just go to show, Kristensen adds, "that we are still very far from knowing the diversity of life on Earth."

Related sites
More about the stick insects, from bugbios.com
The Max Planck Institute for Limnology
The Natural History Museum's entomology department

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