It was only a matter of time before the highly invasive spotted lanternfly (Lycorma delicatula) made its way to western Pennsylvania but it’s disturbing to learn that it’s so close to Pittsburgh.

On 20 January 2020 the Columbus Dispatch reported that spotted lanternfly egg masses were found at the Norfolk Southern railyard in Conway, PA. They probably arrived by train and are now less than 20 miles from Downtown Pittsburgh and even closer to Ohio.

At this time of year the adult bugs are not active so an egg mass, pictured below, is the only thing they found. The authorities scraped away the egg masses and killed the eggs.

This is bad news anyway. USDA says that spotted lanternflies are the worst invasive species we’ve seen in the United States for 150 years.

Learn how to identify them and see why they’re so awful in the video below.

Oh no!

(photos from bugwood.org; click the captions to see the originals)

Ants are amazingly strong for their size, able to lift objects 5,000 times their own body weight and carry them back to the nest. If an object is too big to lift, the ant drags it all the way home.

We’re often so mesmerized by the ant’s struggle that we forget she has an additional challenge. She has to navigate while walking backward. Ethologists at Paul Sabatier University wondered how ants do this so they baked some cookies and ran some tests.

Using a nest of Spanish desert ants (Cataglyphis velox) the scientists laid out large cookie pieces for the ants to find. Without disturbing the ants’ paths scientists noted how often they turned around to check their bearings. They also “airlifted” some ants away from the nest (no path to remember) and messed up the scenery for others so the path would look different.

To give you an idea how hard this is, imagine walking backward without the help of handheld Google/Apple maps. How often would you turn around to check where you were going? And what would you do if an enormous hand rearranged the scenery and nothing looked the same?

Some of the confused ants never made it, but those who knew their path walked 6 meters without peeking. This is equivalent to a human walking backward without peeking for the length of two football fields.

Perhaps it helps that ants can see nearly 360 degrees around their heads. Despite all the challenges they still get home.

Read more in Science Magazine.

p.s. Desert ants don’t use pheromone trails to navigate. Instead they use many other tools including sight, body memory, the Earth’s magnetic field and the scents of other things.

(photo by adrianalexalexander via Flickr, Creative Commons license. Video from Wikimedia Commons; click on the captions to see the originals)

Insects that disappeared in the cold came out again during last week’s warm weather. On Wednesday I found a western conifer-seed bug on my front porch.

Formerly restricted to the western U.S., the western conifer-seed bug (Leptoglossus occidentalis, WCSB) has spread across North America, to Europe and South America. At 1/2 to 3/4 inches this “true bug” sucks the sap of developing pine cones and the pulp of pine seeds.

WCSB can see pine cones from afar in glowing infrared colors so this one was probably lured by the cones on my neighbor’s blue spruce.

After he ate, he needed to find shelter. Wednesday’s warmth was followed by record rain on Thursday and cold wind on Friday.

Western conifer-seed bugs overwinter in a bark crevice, a dead tree, or a house. My house. I didn’t know they came inside until I researched this article. By then the bug had disappeared.

Western conifer-seed bugs stink when they’re disturbed. … Great. I can hardly wait.

(photo by Kate St. John)

So many woolly bear caterpillars have crossed my path this fall that, fearing they’d be trampled, I have carefully moved each one across the trail.

“Woolly bears” are the larva form of a common North American moth, the Isabella tiger moth (Pyrrharctia isabella). Since she is not dependent on only one host plant, Isabella is found in many habitats.

She even lives in the Arctic, surviving the winter because she has natural anti-freeze in her cells. Wikipedia describes how she does it:

The banded woolly bear larva emerges from the egg in the fall and overwinters in its caterpillar form when it literally freezes solid. First its heart stops beating, then its gut freezes, then its blood, followed by the rest of the body. It survives being frozen by producing a cryoprotectant in its tissues.  In the spring it thaws.

— from Wikipedia: Pyrrharctia isabella

After she thaws in the spring, the woolly bear resumes eating, spins a cocoon, and becomes a flame-colored moth.

She’s rather large, but I don’t think I’ve ever seen her as an adult. Have you?

I only notice Isabella as she’s preparing for winter.

Read about woolly bears — and what their stripes mean — in this vintage article: Isabella Scoffs At Winter.

(photos of woolly bear caterpillars by Kate St. John, photos of adult moths from Wikimedia Commons; click on the captions to see the originals)

The orange oakleaf butterfly (Kallima inachus), native to tropical Asia, is well named. The underside looks exactly like a leaf when the butterfly closes its wings, and it has wet and dry season forms that mimic the leaves of each season.

The butterfly stands out when its wings are open.

Watch it become a leaf as it flutters in place.

We have leaf-like butterflies in North America, too. Click to see the ventral and dorsal sides of the goatweed leafwing (Anaea andria). It ranges from southeastern Arizona to southern Ohio.

(photos from Wikimedia Commons; click on the captions to see the originals. video from Red Cache World on YouTube)

While writing about the worldwide spread of Asian ladybeetles (Establishing a Bridgehead) I learned another amazing fact. These insects are cannibals when they need to be, but they’re careful about it. They avoid eating close relatives.

Asian ladybeetles (Harmonia axyridis) are insect carnivores, preferring aphids above all else. Their population surges when aphids are plentiful and goes hungry when aphids crash. Rather than starve, ladybeetle larvae eat eggs and smaller larvae of their own species. The strong ones survive, indirectly regulating their own population.

However, they also make sure that their own family survives …

Interestingly, H. axyridis recognize their kin and are less likely to cannibalize a sibling than a non-related individual (Michaud, 2003). If normal prey becomes scarce, larval mortality can be very high, with in excess of 95% of larvae failing to survive to adulthood, and in such circumstances cannibalism can be essential for survival.

— Invasive Species Compendium, Harmonia axyridis

I’m not surprised that they eat each other, but I’m amazed that they recognize their relatives and avoid eating them.

(photo from Wikimedia Commons; click on the caption to see the original)

Further reading:

• The multicolored Asian lady beetle, Harmonia axyridis: A review of its biology, uses in biological control, and non-target impacts.
• A comparative study of larval cannibalism in three species of ladybird.