This leafminer business all started nearly ten years ago, in the fall of 2011. I had become fascinated with these tiny creatures while I was writing Tracks & Sign of Insects and Other Invertebrates a few years earlier, but it was after visiting Nantucket for the first time, from September 7 to 11 of that year, that I decided to embark on a quixotic quest to create a complete guide to the leafminers of North America, so that I could fully identify everything that I had found there.
During that visit, I met an enthusiastic intern at the Maria Mitchell Association named Eric LoPresti. It was when I returned in November to present my findings at the Nantucket Biodiversity Initiative’s biennial research conference that I met his fellow intern Julia Blyth (now the museum’s consulting collections manager), who has joined me in all my subsequent surveys of the island, as well as on leafminer expeditions all over North America.
In October 2012, in the middle of a three-month voyage around the US, Julia and I explored northern California with Eric for a few days during his first year as a grad student at UC-Davis. In 2017, toward the end of his time there, he invited us out to play in the desert super bloom in southern California, and we spent a week leafminer-hunting with him there and in Arizona. Eric has a knack for finding interesting new mines, and once I tell him something is interesting, he keeps bringing me more and more of it until I have to tell him to stop. One day we discovered previously undocumented leaf mines on sand verbena (Nyctaginaceae: Abronia), a plant for which he has undying enthusiasm, and I thought it would be perfect to name the species after him if I managed to rear it.
I did manage to rear it, but it turned out just to be a new host family for the well-known and extremely polyphagous species Liriomyza trifolii (Agromyzidae).
Later, Eric gave me some leaf mines on Fagonia laevis (Zygophyllaceae), a small-leaved desert plant related to creosote bush. No leafminers were known to feed on this plant, so I was excited to see what the larvae would turn out to be.
They were clearly moth larvae, but to say anything more specific I would have to rear them…
…which I succeeded in doing, but they turned out to be some kind of Gelechiidae in the tribe Gnorimoschemini, a particularly difficult group, so I’ll need to enlist a specialist to figure out what they are more specifically.
But in the meantime, two tiny fly puparia had appeared in the rearing container, and I segregated them out to see what would emerge from them.
Two months later, this female fly appeared…
…and two weeks after that, this male:
Were these weird-looking things agromyzids? I wasn’t sure, but it seemed like they might be, so I threw them in with a big batch of agromyzids I sent to Owen Lonsdale, and when he got a look at them, he reported that they were a new species of Haplopeodes. This is an agromyzid genus I’d never met in person before; in North America there are just four other known species, which are leafminers of Amaranthaceae, Portulacaceae, and Solanaceae and are not known to occur in the Northeast.
Unless you skipped past the title of this post, you won’t be surprised to learn that Owen and I named the new species Haplopeodes loprestii, in a paper that was published this week*. The other twelve species described in this paper were reared by our three coauthors: John van der Linden, Tracy Feldman, and Mike Palmer. Coincidentally, last fall Eric moved to Oklahoma, where he is now an assistant professor at Oklahoma State University, filling the position that became available when Mike Palmer retired and moved to Oregon.
So what does Haplopeodes loprestii do for a living? It’s probably a leafminer, since all its known relatives are, but since the rearing container included Fagonia stems and fruits as well as leaves, it’s conceivable that the larvae feed in one of these other structures. The leaves are so small that if there were two different types of mines in them, it would have been hard to notice—and I didn’t know to look until the leaves were too far gone to try. Always more to learn!
* Eiseman, Charles S., Owen Lonsdale, John van der Linden, Tracy S. Feldman, and Michael W. Palmer. 2021. Thirteen new species of Agromyzidae (Diptera) from the United States, with new host and distribution records for 32 additional species. Zootaxa 4931(1): 1–68.