Visiting the Weevil Course & Roundup in 2025

By Jakob Jilg

Arrival (July 20)

After departing from Frankfurt, Germany, and changing flights in New York, I had the most wonderful landing approach to Phoenix, AZ! It was about sunset, and the plane was descending through an unreal world of golden clouds. One of those moments where you feel small, yet embraced by wonder. I was relieved that my precious beetles hadn’t been seized in New York, as everything had been correct with my declaration. Now there was nothing to worry about. My head was swirling with anticipation about all the nice people I would meet and the weevils I would see. From time to time, windows of crystal-clear air opened between the flaming clouds and allowed me to glimpse yet another strange world: the desert hills! Erosion works differently there, and I had never seen a landscape quite like it before. What will the weevils there be like, I wonder?

After arriving at the motel, I was welcomed on the parking lot by Samuel Brown. We immediately started nerding out over weevils with great enthusiasm, even though it was late at night.

The first days in Tempe (Jul 21 – Jul 24)

Jennifer Girón had asked me if I’d like to join a few days ahead of the course, to help pulling a synoptic set of specimens from the O’Brien collection at Arizona State University (ASU). Of course I‘d like to do that! I was eager to see the collection of Charles O’Brien, a name familiar through his checklists for Central- and North American weevils.

One of the main objectives of the Weevil Course was to test and practice keys to genera of North American weevils. To have suitable material at hand, we loaned a synoptic set of specimens representing about 500 genera! 

But before starting with that, Jennifer, Samuel and I spent the first day at the ASU library, entering weevil data into TaxonWorks. It proved to be an excellent way to kickstart my learning of the platform. It’s so much easier to learn something face to face!

The next days were spent entirely at the collection, gathering the specimens with Lourdes Chamorro and Salvatore Anzaldo. We also met with Sangmi Lee (curator of the O'Brien Collections), Alexis Cortés Hernández (another student for the weevil course) and Matt Buffington (a wasp expert who joined us to halp with course logistics and imaging).

The collection is housed in a building with a friendly interior, radiating a mood unique to only a few institutions: This is not a place where people are crushed by academia. It appears not tainted by the past in the way many older (European) museums are. This is a place to evoke fascination, a place where eyes are opened and where personal journeys begin. It is also the first insect collection I’ve seen with a carpet floor.

On the last day, after the material was gathered, there was even a bit of time left to indulge in the collection. I used that time to verify identifications for the weevils that I had collected in Panamá.

The next morning, the synoptic set was loaded into a rental van, along with a barrel of ethanol, and we were ready to embark on the 400 km drive to the Southwestern Research Station! The name of the locality, Portal, was not unfamiliar to me. When I worked at the Museum für Naturkunde in Berlin, I used to mount hymenopterans from Portal whenever I did home office. I had seen insects from Portal, now I’ll see where they came from!

The Weevil Course & Roundup (July 24 – August 2)

The weevil course had last been offered 10 years before. The 9-day course provides knowledge and resources for weevil identification at the subfamily level, highlighting relevant characters for genus-level identifications. As the instructors are involved in the preparation of a new volume for “Beetles of Canada and the United States”, the course was also an opportunity to test the updated keys to genera. The course covered basic taxonomy of weevils, their biology, current classification, collecting methods, and curatorial and identification techniques. Students and instructors were able to collect and keep the specimens they collected and identified for their own reference collections.

There were 18 participants and 10 instructors. The research station provided three meals a day, and in between we had a schedule of lectures, identification training, and field work. 

Each lecture would focus on one taxonomic group of weevils. We learned about their phylogeny, classification, morphological characters and life history. It also became clear how tentative much of our knowledge about weevils is. The monophyly of most groups had never been thoroughly tested, either by molecular phylogeny or by morphological analysis. But regardless of phylogenetic reality, it is important to know how weevils were classified in earlier times, to be able to use resources of the past, such as catalogs and keys. After each lecture, we fetched some specimens from the synoptic collection belonging to the group we had just learned about (or used those we collected ourselves), and ran them through the key to genera. This is where the high proportion of instructors proved most helpful, as in any taxonomic course. To get started, some specimens were placed under a microscope equipped with a camera, allowing everyone to follow along on the screen while interpreting characters together as a group.

The lectures were extremely well done! It was very interesting for me to get a deep insight into the North American fauna, which is unfamiliar to me and differs from the European fauna in intriguing aspects. For example, Baridines are known as “flower weevils” in North America. No one would call them such in Europe, as our species show no particular interest in flowers (at least to my knowledge)! In this context, I’m really looking forward to see the phylogeny of Baridines that will be a result of the PhD thesis by course participant Rina Talaba.

Learning about the diversity of weevils during the lectures also incited motivation to go collect them. We heard about strange weevils and how to find them.

One genus that seemed to captivate absolutely everyone was Gerstaeckeria, cryptorhynchines associated with cacti, most of them on prickly pears and chollas. 

Cryptorhynchines always had a special place in my heart, and I’m sure that’s not just me. Many are associated with dying or dead wood, inheriting some imagery I associate with their habitat: old-growthness, the darkness of old forests and nocturnal lifestyle as well as the damp, hidden world of the leaf litter zone. While many cryptorhynchines also occur in secondary habitats, the flightlessness of numerous species makes their presence dependent on the history and connectivity of the landscape. Their presence or absence can tell stories and stir the imagination. How did you get here, little weevil?

The name “Cryptorhynchinae” (kryptós “hidden” and rhýnchos “snout”) is pointing out their most striking feature, the habit of retracting the rostrum into a rostral channel for protection. It’s not only the rostrum that is hidden, the weevils themselves tend to have a cryptic lifestyle. As a result of them blending with their environment, they look like a tiny landscape themselves. They bear ridges and valleys, covered by bristles and setae, just as the forest floor is covered by decaying twigs and branches. You don’t see them unless you actively search, often involving leaf litter sifting and nightly excursions.

Of course everyone wanted to see Gerstaeckeria! Especially after rumors spread that specimens had already been found even on the grounds of the station!

After some unsuccessful searches, one night a group of us was out in the surroundings of the station. When the first Gerstaeckeria was found beneath a dead pad of a small prickly pear, everyone gathered around quickly. Then suddenly, one by one, everyone spotted one! We were shouting with excitement!

Throughout the course, we visited the following main localities, some several times, also both at day and night: 

While collecting, I noticed again how important it is to know about host plants. Of course beating random plants is yielding weevils, but learning about a specific plant with a specific weevil, and then targeting that plant, is generally more successful. Because of this, I always asked others what plants they’ve been sampling and what they found on those plants. In preparation of a future course, it would be an idea to make a list of plants and their weevils for the Chiricahuas, that could be handed out to students.