Citizen Science Leads to Discovery of New Wasp Species on Garden Grounds

The newly identified Druon laceyi along with the leaf galls that provide them food and shelter.

Many Fort Worth and area residents have explored the Garden for years. They may think they know every corner, every path and every tree.

In fact, our own Garden holds many surprises. For example, a new species of gall wasp was recently identified on Garden grounds. The story of the wasp’s discovery has much to tell us about the importance of citizen science, the diversity of life around us and the many mysteries waiting to be uncovered in our own backyards.

Introducing the Gall Wasp

Gall wasps are tiny insects, often about the size of a mosquito, in the Cynipid family. They get their common name from a distinctive part of their lifecycle. Gall wasps lay their eggs on trees and then induce the tree to grow a layer of tissue around the egg called a gall. (The mechanism behind this process is still unknown.) When the eggs hatch, the larvae, safe from predators, eat the tissue of the gall to grow. In time the larvae transform into adult wasps, which then break out of their small, safe home into the wide world.

They don’t have much of a life after that, although presumably it is satisfying enough for the gall wasp. If they can avoid being eaten by birds, lizards or other predators, the primary goal of a male wasp is to find a female wasp. The goal of a female wasp is to lay eggs that will begin the process all over again. Females don’t always need male wasps to help in this process; many gall wasps reproduce asexually.

The newly discovered wasp is about 2.2 mm long, about the size of a small mosquito.

One reassuring fact for humans who usually run screaming from all things wasp-related: gall wasps don’t sting.

Different wasps lay eggs on different plants, and each gall is different. Some form large lumps on tree limbs, others create fruit-like balls that hang from branches, and still others appear as small hard bumps on leaves. Oak trees are favorite habitats of gall wasps, although they can grow on a wide variety of trees and herbaceous plants.

Discovering Druon laceyi

Kimberlie Sasan, BRIT herbarium and research assistant, first grew interested in gall wasps as an outgrowth of her long fascination with moths. She soon realized that identifying the wasps was difficult, even when working with scientists and amateur naturalists on online forums such as iNaturalist, a social network that allows users to crowdsource species identification and record the occurrence of plants, animals, insects, fungi, etc.

“I’ve been very active on iNaturalist for a long time, but then I started finding these galls that no one could identify,” says Sasan. “I would post photos and ask if anyone had seen anything like it, was this new, could anyone help? In time, a community grew up of people fascinated with these wasps.”

Another frequent user of iNaturalist and individual interested in gall wasps is BRIT Research Assistant Bob O’Kennon. In 2020, O’Kennon contacted Sasan about a gall wasp he had discovered on a lacey oak (Quercus laceyi) on the Garden grounds. Sasan agreed that she had never seen anything like this particular wasp.

Sasan’s next step was to take some the galls home in the fall of 2020 and tend them until the adult wasps hatched in the spring of 2021. This allowed her to photograph the insect and preserve several of the wasps for further study.

Scanning electron microscope images reveal minute details of the wasp’s head. Images like this help scientists categorize and differentiate different species.

The next step was to involve an insect expert. Sasan and O’Kennon worked with entomologist Y. Miles Zhang with the US Department of Agriculture Systematic Entomology Lab. Zhang further studied the wasp and conducted genetic testing to establish that this was a novel undescribed species. The paper announcing their results was published July 20 in the journal Zootaxa.

More to Discover

Sasan anticipates many more species of gall wasps await official recognition by science. Sasan is one of the founders of a website devoted to the identification of insects that form galls, called gallformers.org, and she is aware of dozens, if not hundreds, of the insects that remain unidentified.

In fact, it seems that whenever experts go looking for gall wasps, they find them. A January 2022 article in Texas Monthly describes the work of Rice University associate professor Scott Egan, who, with his students, has discovered multiple species of previously unknown gall wasps on campus oak trees. Scientists have only begun to understand the diversity of this family of insects.

“It’s such an open field,” says Sasan. “We don’t know what’s ahead of us–and it’s really exciting.”

It’s also a good reminder that even the places we think we know are teeming with hidden wonders waiting to be discovered.

Related Articles

Sunflowers by sign that reads Embrace New Beginnings
Learn

Community Education Fall Preview: Grow Your Mind with New Classes and Workshops

It still feels like the height of summer, but fall is just around the corner, and that means the Community Education program is rolling out a new slate of classes, workshops and events. “We’ve got a mix of long-time favorites and completely new experiences,” says Community Education Manager Crissa Nugen. “I think almost everyone will find something they want to explore.”

Read More »
Water sprinkler on summer day
Garden

Managing Your Garden Through Heat and Drought

Gardeners across North Texas can only look at their landscape and sigh as the heat wave refuses to break and rain refuses to fall. Plants that thrive most summers are withering and dying under the stress of week after week of 100-degree-plus temperatures. Gardeners struggle to balance watering enough to keep their plants alive with responsible behavior during a drought–and the prospect of budget-busting water bills. What to do? “The first step is to not give up,” says Sr. Horticulturist Steve Huddleston. “You do have options.”

Read More »
Newsletter

Early Childhood Program Heads Back to School, Bringing Nature-Based STEM Learning to Pre-K Students

Most area school districts begin classes this month. Alongside all of the students and teachers, those heading back to the classroom include members of the FWBG | BRIT early childhood education team. They will spend the school year helping some of the youngest learners in our area explore the outdoors. “Our goal is to help teachers incorporate nature into learning for three-year-old pre-k students,” says Early Childhood Program Manager Cheryl Potemkin.

Read More »
Engage

Explore the Garden’s Refreshing Water Features This Summer

The blazing summer heat shows no sign of relenting, and it’s safe to say that most area residents are fed up with 100-degree-plus temperatures. Since there’s not much we can do except wait for fall, we here at the Garden invite you to find refreshment at our many ponds, fountains and streams.

Read More »
Newsletter

Teach Observation Skills this Summer with Three Simple Prompts: I Notice, I Wonder and This Reminds Me

The scientific method begins with observation, yet observation isn’t often taught. Parents and teachers assume that students know how to observe without explaining that observing isn’t simply looking. It’s a way of engaging with the natural world that employs multiple senses, draws on existing knowledge and raises questions for further discussion. Learn more about how to teach your children how to observe.

Read More »