Wood Wasp Size Comparison and Fossil Record

Wood wasps are relatively small insects, but their size can vary significantly depending on the species. Some wood wasps, like the Sirex woodwasp, can grow up to 2.5 inches in length.

The largest wood wasp species, the Sirex woodwasp, is found in North America and Europe. Its impressive size makes it a notable exception to the general rule that wood wasps are small.

In comparison, the smallest wood wasp species, the Xiphydria species, is only about 0.2 inches long, making it barely visible to the naked eye. This tiny size is a testament to the incredible diversity of wood wasp species.

The fossil record shows that wood wasps have remained relatively unchanged in size over millions of years.

A different take: Giant Wood Wasp

Giant horntail wood-wasps lived 53 million years ago in what is now British Columbia, Canada. They were herbivorous and flew through the landscapes.

The fossilized remains of a previously unknown horntail wood-wasp species were discovered in the McAbee Fossil Beds near Cache Creek, British Columbia, Canada. This species, named Ypresiosirex orthosemos, represents a completely new genus.

The fossil horntail wood-wasp resembles its modern relatives and is in remarkable condition. It measures almost 3 inches in length, which is considered gigantic.

Many of the trees and other plants that modern horntail wasp young burrow in have been found as fossils in the same locations as the ancient wasps. This includes fir, pine, spruce, hemlock, sequoia, cedar, and possibly juniper.

The climate was right for these insects, too. The average temperature in the McAbee forest would have been much like that of modern Vancouver, which wasps find agreeable.

See what others are reading: Wood Boring Wasp Identification

Urocerus gigas is one of Britain's largest sawflies, with a female body length that can reach 40 mm.

The females are black and yellow with yellow antennae and yellow tibiae and tarsi, making them quite distinctive.

Males have a black thorax and mostly red abdomen, which is a notable difference from the females.

The hind legs of males are darker and thicker than those of females, and they can be distinguished from males of most other Urocerus species by the widely separated yellow spots behind their eyes.

A unique perspective: B Size Battery

Females are often seen on fallen conifer trunks and log piles, where they can be found ovipositing and depositing a mutualistic fungus to help their larvae digest wood.

The larvae of Urocerus gigas develop in the timber of conifers, including pines, larches, and spruces, and can be considered a timber pest in various parts of the world.

Males are less frequently seen and tend to spend most of their time in the tree canopy, although I once saw dozens of swarming U. gigas males in a factory tower in Coventry, far from any coniferous woodland.