On May 8 last year, Julia and I visited her family’s land in Hocking County, Ohio (which we’ll be doing again today, as it happens), and for whatever reason, a little clump of dead wingstem (Asteraceae: Verbesina alternifolia) stems from the previous season caught my eye. I’m always amazed by all the things John van der Linden is able to find living inside of plant stems when there is little or no external evidence, and occasionally I’m moved to split a stem open at random and see what there is to see. So I got out my trusty Swedish army knife, started splitting one of these wingstem stems open, and behold! Something had been tunneling in the pith.
A little more splitting turned up what I was hoping to find: puparia of a Melanagromyza species; one of the so-called “leafminer flies” (Agromyzidae) that is a stem borer instead of a leafminer.
But the fly larvae hadn’t been the only things tunneling in there. As Julia and I split open additional stems, we also found several larvae and pupae that I thought might be Mordellidae: “tumbling flower beetles.”
Naturally, we collected the chunks of stem containing these immature insects in vials to see what they would turn into. The first thing to emerge, on May 18, was this gall midge (Cecidomyiidae):
This was not unexpected; the second Melanagromyza puparium shown above was at the edge of a slight swelling in the stem that I had thought might be a midge gall. Ray Gagné has confirmed that this midge is Neolasioptera imprimata, a species he had described just two years earlier. Here’s a better look at the gall:
Just to the right of the center of the above photo, the midge’s pupal skin can be seen poking out of the gall. A closer view:
Beginning two days later, 22 platygastrid wasps emerged from the same gall—and I only collected half of the gall, so there were probably even more midges and wasps in the other half. Jessica Awad tells me these wasps belong to the genus Platygaster, and that a species ID is unlikely to be possible anytime soon given the current state of knowledge of this genus. All platygastrid wasps (as the family is currently circumscribed) are parasitoids of gall midges.
Also on May 20, an adult mordellid beetle appeared, proving my hunch right. As far as I can tell, there is no one who studies these beetles or knows how to identify them, but this one is now in the Canadian National Collection if anyone wants to have a look at it.
On June 13, two more wasps emerged. One was a braconid parasitoid of the mordellid beetles, which Gideon Pisanty identified (based on photos I posted on iNaturalist) as a member of the tribe Brachistini (Brachistinae).
The other was this figitid wasp, which I recently sent to Matt Buffington along with 50 or so others I’ve accumulated over the past few years, and he hasn’t had a chance to look at it yet. It emerged from one of the Melanagromyza puparia.
Something dark developed inside the other Melanagromyza puparium, but nothing ever emerged from it.
According to Spencer & Steyskal (1986), the only stem-boring Melanagromyza known from wingstem (or any other Verbesina species) is M. verbesinae, which Owen Lonsdale synonymized last year with M. vernoniana—a species that, based on the specimens Owen examined, feeds on other Asteraceae including ironweed (Vernonia), sneezeweed (Helenium), sunflower, and Jerusalem artichoke (Helianthus). Spencer & Steyskal described the puparium of M. verbesinae (the holotype of which was collected in Ohio) as “straw colored, posterior spiracular plates heavily chitinized, closely adjoining, only narrowly divided, each with ellipse of about 12 bulbs around strong central horn.” This seems to fit what I found, so I’ll choose to believe that the flies I failed to rear were M. vernoniana and not something new and exciting that I need to try to find again today.
For more on the fascinating world of stem-dwelling insects, about which I know very little, check out this document John van der Linden recently put together summarizing all the agromyzid flies he’s found in this microhabitat. And you can learn about the other flies, moths, beetles, etc. he’s found living in stems by perusing his photos on BugGuide.
Someone asked me the other day how many new species I’ve found, and I realized that in addition to not being able to give a straight answer for the reasons discussed below, I’d lost track of how many species I’ve helped to describe and name, which is a question that at least has a definite answer. So here’s an update of my original “How Many New Species?” post from three years ago. It’s been fun to see people finding some of these species all over the US and Canada as I peruse the leafminer observations on iNaturalist.
I am often asked how many new insect species I have found (or “discovered”). I’m never quite sure how to answer this. I’ve certainly reared dozens of undescribed species of moths, for instance, that are now sitting in my office or in various museums, waiting to be named. The number for parasitoid wasps is probably even higher. But simply having “found” new species doesn’t count for much if they haven’t been properly documented and named. Also, to me the credit for “discovering” a new species mostly belongs to the taxonomist who does the hard work of comparing it with all the similar species in the world to demonstrate that it is really something new. Of all the species I have coauthored, Marmara viburnella is the only one I felt certain was undescribed (because I went to the trouble of reviewing the larval biology and adult morphology of all the previously described species in that genus) before I passed it along to a taxonomist.
With that said, for my final post of the year, I thought it would be fun to put together a list of all the species that have been either described in papers I coauthored or described based (at least in part) on specimens I collected. (This was partly inspired by my realization that I never got around to writing anything here about most of the 30 fly species I recently described with Owen Lonsdale.) With any luck, this list will continue to grow. What limits the number of new species I’m able to help describe is a shortage not of “new” species to name, but of time that my collaborators and I have available to devote to this task. So the take-home message from this post should not be “Wow, look at all the new species Charley has found!”, but rather, “Wow, we have so much left to learn about our natural surroundings, and we need to support more funding for taxonomy!”
For species I’ve written about before, you can click on the name to see the relevant post.
First, the species I did not coauthor (of these, Orchestomerus eisemani and Adelius floridensis are the only species for which one of my specimens was designated as the holotype):
1. Celticecis cornuataGagné, 2013 – A hackberry gall midge I found in Kentucky while traveling with Noah to check out the periodical cicadas in Nashville and Sam Droege’s bees in Maryland.
2. Orchestomerus eisemani Yoshitake & Anderson, 2015 – A leafminer of Virginia creeper I found at work one day in Plymouth County, Massachusetts. This seems to be pretty close to its northeastern range limit; if you check the map on iNaturalist you can see that I ‘ve since found it as far north and west as Concord, but no sign of it yet anywhere in western Massachusetts or more northern states.
3. Brachys howdeni Hespenheide (in Hespenheide & Eiseman, 2016) – I first found this trailing arbutus leafminer while hiking along the ridge just above the house where I now live. I see the mines in just about every sizable patch of the host plant I encounter.
4. Liriomyza limopsis Lonsdale, 2017 – Owen had already given this species a name based on Canadian specimens collected as adults, but no host plant was known until I reared it from white wood aster (Eurybia divaricata) and whorled aster (Oclemena acuminata) in New York and Massachusetts.
5. Liriomyza pilicornis Lonsdale, 2017 – Similar story, except that Graham Griffiths was the first to rear this species, 45 years before Julia and I found it mining leaves of bastard toadflax (Comandra umbellata) in Massachusetts.
6. Liriomyza pistillaLonsdale, 2017 – Ditto, except in this case the host is cow-wheat (Orobanchaceae: Melampyrum lineare) and Griffiths reared it 40 years before me. I find the leaf mines pretty regularly.
7. Adelius floridensis Shimbori & Shaw, 2019 – This braconid wasp species is known only from a few specimens I reared in 2013 from the St. Johnswort leafminer Fomoria hypericella (Nepticulidae) in Florida.
So that’s seven in the first category. I mostly just happened to give specimens to the right taxonomists at the right time: Ray Gagné was finishing up a revision of all the gall midge species on hackberries; Henry Hespenheide was (and is) in the midst of revising the genus Brachys, and Owen Lonsdale was finishing up a revision of the Canadian species of Liriomyza. In the case of Orchestomerus eisemani, Bob Anderson was inspired to revise that genus after having initially identified the weevils I had reared as O. wickhami Dietz, then discovered his error after I had published a note documenting their natural history. Adelius floridensis got to be described because Dave Wagner directed Scott Shaw and Eduardo Shimbori to me when they asked him if he had any specimens they might use in their revision of the New World braconid wasps of the tribe Adeliini. For the 76 species listed below that I have coauthored, I’m extremely grateful to the taxonomists who took time away from whatever other projects they were working on to help me put names to my natural history observations.
1. Scolioneura vaccinii Smith & Eiseman (in Smith et al. 2015) – A sawfly that mines leaves of huckleberries (Vaccinium spp.), which Julia and I found in western Washington on our first cross-country trip in search of leafminers (though we only were able to rear parasitoids, and the type specimen was reared from a larva Noah and his wife Sydne collected the following year).
2. Megaselia nantucketensis Eiseman & Hartop, 2015 – A scuttle fly that emerged from a midge gall on black oak, collected on Nantucket during the gall and leaf mine survey I’ve been conducting there since 2011.
3. Megaselia risoria Hartop, Wong & Eiseman, 2016 – The naming of this species was a byproduct of my having reared specimens of M. globipyga from a dead tussock moth caterpillar I found at work.
4. Platygaster pruni Buhl & Eiseman, 2016 – A platygastrid wasp that emerged from a midge gall on black cherry, which I collected at work one day in western Massachusetts.
5. Platygaster uvulariaeBuhl & Eiseman, 2016 – A platygastrid wasp that emerged from a midge gall on wild oats (Uvularia sessilifolia)—again collected at work in western MA. No one has yet been able to rear the midge that causes this gall.
6. Platygaster vitisiellae Buhl & Eiseman, 2016 – A platygastrid wasp that emerged from a midge gall on wild grape, collected as part of the Nantucket survey. The midge species is probably undescribed (but I was able to rear some adults, which are sitting in the Smithsonian waiting for someone to decide to revise the genus Vitisiella).
7. Zygoneura calthella Eiseman, Heller & Rulik, 2016 – A dark-winged fungus gnat that feeds in leaves and petioles of marsh marigold. Julia and I first found it while surveying for four-toed salamanders in western Massachusetts.
8. Fenusa julia Smith & Eiseman, 2017 – A sawfly that mines leaves of wild rose, which Julia spotted in Colorado on another leafminer-hunting road trip.
9. Marmara viburnella Eiseman & Davis (in Eiseman et al. 2017) – Another product of the Nantucket survey. The larva of this moth begins as a leafminer, then disappears down the petiole and spends most of its life feeding in the stem. Julia and I reared it from arrowwood, but mines have also been found on various other viburnums.
10. Platygaster tephrosiae Buhl & Eiseman, 2017 – Another one from Nantucket; I reared the two known specimens from midge galls that happened to be on some goat’s rue leaves that Kelly Omand collected for me to feed some leaf-tying caterpillars. I failed to rear the caterpillars, and I haven’t been able to rear the midge yet either.
11. Platygaster vacciniiBuhl & Eiseman, 2017 – The single known specimen emerged from a gall on lowbush blueberry that I collected at the 2016 Berkshire BioBlitz on Mt. Greylock—caused by another midge that has never been reared.
12. Macrosaccus coursetiae Eiseman & Davis, 2017 – Another one Julia and I collected on our first cross-country trip; this one from Arizona, mining leaves of a shrub called rosary babybonnets (Coursetia glandulosa).
13. Phytosciara greylockensis Eiseman, Heller & Rulik, 2018 – Another one from the Mt. Greylock BioBlitz; a dark-winged fungus gnat that mines leaves of bluebead lily (Clintonia borealis).
14. Agromyza fission Eiseman & Lonsdale, 2018 – Owen had already named this species based on a specimen collected in the DC area in 1914, but the type specimen is one Julia and I collected at MJ Hatfield’s “Red Oak Prairie” in eastern Iowa on the way home from Colorado. One of the paratypes came from a larva we collected the next day on Marcie and Mike O’Connor’s land in Wisconsin, and Mike Palmer provided two from Oklahoma. The larvae mine leaves of hackberry.
15. Agromyza sokaEiseman & Lonsdale, 2018 – This is another one that Owen had already named based on a 1914 specimen from the DC area, but as with A. fission its host was unknown. It turns out to be responsible for leaf mines on black locust that since 1982 have been attributed to Phytoliriomyza robiniae (Valley), adults of which were repeatedly associated with black locust but never actually reared. Some paratypes came from specimens Julia and I reared from larvae we collected at the 2016 Connecticut BioBlitz, and the rest came from larvae Tracy Feldman found mining both black locust and wisteria in North Carolina.
16. Melanagromyza palmeri Eiseman & Lonsdale, 2018 – The only known specimen is one that Mike Palmer reared from a sunflower stem (or possibly the roots) in Oklahoma. Stem feeding members of this genus are borers rather than miners, meaning that they don’t form any externally visible trails. So rearing them takes special dedication and/or luck.
17. Ophiomyia euthamiaeEiseman & Lonsdale, 2018 – This species mines leaves of grass-leaved goldenrod (Euthamia graminifolia), mostly on the lower surface. I first noticed mines like this on Nantucket, but those were possibly made by O. maura; the whole type series of O. euthamiae came from my yard.
18. Ophiomyia mimuliEiseman & Lonsdale, 2018 – This species mines in stems of monkeyflower. I first found it at a bioblitz on Julia’s family’s land in southern Ohio, and some paratypes came from the swampy woods right behind our house in Massachusetts.
19. Ophiomyia pardaEiseman & Lonsdale, 2018 – Another species whose holotype I collected in my yard. It is a common leafminer of asters (Symphyotrichum spp.) and seems to be responsible for all of the mines previously attributed to O. quinta.
20. Calycomyza artemisivoraEiseman & Lonsdale, 2018 – This species is known only from two specimens I reared from leaf mines on Artemisia ludoviciana that Mike Palmer collected in Oklahoma.
21. Calycomyza aviraEiseman & Lonsdale, 2018 – Another one that Owen had already named before I reared it; there are several specimens at the Smithsonian from Connecticut, New York, and West Virginia, dating back to 1929. The larvae mine leaves of beggar-ticks (Bidens spp.). I reared some from mines I collected at work, and Tracy Feldman provided some from North Carolina.
22. Calycomyza eupatoriphagaEiseman & Lonsdale, 2018 – This belongs to the same species complex as C. artemisivora. It has been reared from three plants in the tribe Eupatorieae: I found it on white snakeroot (Ageratina altissima) in Massachusetts and on blue mistflower (Conoclinium coelestinum) in Tennessee, and Mike Palmer found it on late boneset (Eupatorium serotinum) in Oklahoma. In teasing apart the members of this complex, Owen found a specimen that was collected in Ontario in 1947, which he included as a paratype. The holotype is from the woods right behind our house.
23. Calycomyza vogelmanniEiseman & Lonsdale, 2018 – I reared the only known specimen from a leaf mine on thin-leaved sunflower (Helianthus decapetalus), which I collected near Burlington, Vermont, where I went to grad school. I named the species after Hub Vogelmann, who founded my graduate program (the Field Naturalist program). He had retired long before I attended, but he was very enthusiastic about my first book when it was published, and he was supportive as I got started on my leafminer book project.
24. Cerodontha edithae Eiseman & Lonsdale, 2018 – This species is an iris leafminer, the only known specimen of which Julia and I reared as part of our Nantucket surveys. I named it after Edith Andrews, who died in 2015, a day after her 100th birthday. She lived on Nantucket for most of her life and was an enthusiastic naturalist to the end. Birds were her main passion, but not long after Julia gave her a copy of my book, Julia went to visit her and found her and her daughter Ginger on their hands and knees in her driveway, getting a closer look at some wasp burrows. When I first met her, I was amazed at the memory of this nearly 100-year-old woman as she quoted from various parts of my book.
25. Cerodontha feldmaniEiseman & Lonsdale, 2018 – Another species known from a single specimen; in this case one I reared from a sedge leaf mine that Tracy Feldman collected in North Carolina. Tracy has been intensively collecting leafminers in North Carolina and elsewhere for the past few years and has found numerous new state records, new host records, and new species.
26. Liriomyza ivorcutleri Eiseman & Lonsdale, 2018 – I reared the holotype from a leaf mine on cup plant (Silphium perfoliatum) that Julia and I found in Iowa. When Owen told me this yellow fly was a new species, I couldn’t resist naming it after Ivor Cutler, the Scottish recording artist responsible for “Yellow Fly,” along with other classics like “I Believe in Bugs.”
27. Liriomyza valerianivoraEiseman & Lonsdale, 2018 – I found the leaf mines of this species in a scrappy wetland in north-central Massachusetts where I was conducting botanical fieldwork with Sally Shaw. I was lucky she was with me, because I never would have recognized the basal leaves of garden valerian, which are totally different from those on mature plants.
28. Phytomyza actaeivoraEiseman & Lonsdale, 2018 – I tried for several years to rear adults from leaf mines on red baneberry (which I’ve found in Vermont and Ohio) before finally succeeding with some mines I found on white baneberry in my neighbors’ woods. I also found mines of what is probably the same species on black cohosh (these are all Actaea species) at Jason Dombroskie’s house in Ithaca, NY, but these were all parasitized like the ones on red baneberry.
29. Phytomyza aesculiEiseman & Lonsdale, 2018 – I first became aware of this species because of photos of buckeye leaf mines that several different people posted to BugGuide.net. One spring when Julia was visiting her parents in Ohio (the Buckeye State), she managed to collect a bunch of larvae, from which I reared the type series. This species is active only in spring, with a pupal diapause lasting nearly a year. The author of this article was grateful when I let him know that his mystery “buckeye leafmining fly” now has a name.
30. Phytomyza confusaEiseman & Lonsdale, 2018 – I named this fly “confusa” because everything about it was confusing. I found the leaf mines at the base of a tree in the middle of a lawn in a big park in Iowa. I tentatively identified the plant as Virginia waterleaf (Hydrophyllum virginianum), but it looked a little weird to me (not to mention that Virginia waterleaf is normally a forest species). Iowa botanist John Pearson suggested that it might be a buttercup such as Ranunculus fascicularis. When Owen initially determined the flies as belonging to a new species in the Phyomyza aquilegiae group, this seemed to fit, since all members of this group feed on plants in the buttercup family as far as is known. I showed my photo of the plant to several other botanists, and they all shared my initial impression that it was Virginia waterleaf, but most were also willing to believe it was Ranunculus fascicularis, and one even examined some herbarium specimens of that species that she said matched in every respect. But Owen later determined P. confusa to be closely related to another new species that I reared from two species of waterleaf (see below), and decided both flies probably are better placed in the P. obscura group, all species of which feed on plants in the mint and borage families (waterleafs are in the latter). This species was also confusing because the leaf mines were hard to characterize—some began with a distinct linear portion and some did not, and by the time the adults emerged the leaves were so crumpled and degraded that I couldn’t decide whether the puparia were formed inside or outside the mines. John van der Linden has since repeated the rearing of this species from Virginia waterleaf, so so the identity of its host plant is no longer a point of confusion, but other details of its biology are still unclear.
31. Phytomyza doellingeriaeEiseman & Lonsdale, 2018 – While working in Maine in July 2013, I collected leafminers from flat-topped aster (Doellingeria umbellata) that Owen determined to be a new species near P. solidaginivora Spencer based on the genitalia. Both of the adults I reared were underdeveloped (as shown here), so when I returned in August I collected some more. I reared some good specimens this time, but Owen determined them to be a different new species, which I named P. doellingeriae. Meanwhile, he decided the first flies were close enough to P. solidaginivora to call them that for now. Incidentally, Spencer (1969) reared P. solidaginivora from a plant in Alberta that he thought was goldenrod (Solidago; hence the name), but Graham Griffiths examined his pressed leaf mines and didn’t think they looked like any goldenrod that occurs in Alberta. Spencer’s drawing of the leaf looks exactly like a flat-topped aster leaf, so that fly is probably misnamed.
33. Phytomyza hatfieldaeEiseman & Lonsdale, 2018 – When Julia and I stayed with MJ Hatfield in northeastern Iowa on the way home from Colorado, we spent a little time exploring the woods on the bluff next to her house with MJ and John van der Linden. Leaf mines that we collected there on sweet cicely (Osmorhiza claytonii) yielded the holotype of this new species. The paratypes also included a number of specimens Graham Griffiths had reared from various Osmorhiza species in the 1970s, plus a few that Ed Stansbury reared in Washington just in time to be included in the paper.
34. Phytomyza hydrophyllivoraEiseman & Lonsdale, 2018 – This species is common on broad-leaved waterleaf (Hydrophyllum canadense) in Ohio, and I collected the mines several times from the woods by Julia’s parents’ house before I finally got a few adult flies instead of parasitoid wasps. I later reared one from the same host in Tennessee (during our brief trip to see the solar eclipse in 2017), and one from a mine I found on Virginia waterleaf while conducting a rare plant survey in the Berkshires.
35. Phytomyza palmeriEiseman & Lonsdale, 2018 – This is another species (like Melanagromyza palmeri) known only from Mike Palmer‘s yard in Oklahoma, and although he gave me a number of leaf mines, only he has been able to rear adults. The larvae mine leaves of coralberry (Symphoricarpos orbiculatus).
36. Phytomyza palustrisEiseman & Lonsdale, 2018 – I found this leafminer of swamp saxifrage while conducting botanical fieldwork in the Berkshires. I check this plant for mines every time I see it, but as far as I can tell the range of this species is limited to one square meter in the town of Washington, MA.
37. Phytomyza sempervirentisEiseman & Lonsdale, 2018 – Julia and I first found this species when we visited Cane Creek Canyon in northern Alabama on our way home from Florida in spring 2013. The larvae form mines on coral honeysuckle (Lonicera sempervirens) very similar to those formed by the closely related P. nigrilineata (Griffiths) on limber honeysuckle (L. dioica) in Alberta. I found more (including the holotype) three years later at the Montague Plains in western Massachusetts. Tracy Feldman also provided a bunch of specimens from North Carolina, and Mike Palmer reared a few from orange honeysuckle (L. ciliosa) in Oregon.
38. Phytomyza tarnwoodensisEiseman & Lonsdale, 2018 – I reared the only known specimens of this species from leaf mines on bush honeysuckle (Diervilla lonicera) I collected in my parents’ yard in western MA. “Tarnwood” is the name my parents gave to their property many years ago, and when I was little this sign that my mother painted used to be on a post at the edge of our yard by the road:
39. Phytomyza tigrisEiseman & Lonsdale, 2018 – The larvae of this species mine leaves of foamflower (Tiarella cordifolia). The leaf mines are very common, but it took me many tries (always getting only parasitoid wasps) until I finally managed to rear a few adults—in my neighbors’ woods right near where I finally found unparasitized puparia of P. actaeivora. The name Phytomyza tiarellae was already taken, so I named this one “tigris” after the tiger stripes on its puparium (going with the “big cat” theme Owen had started with Ophiomyia parda).
40. Phytomyza triangularidisEiseman & Lonsdale, 2018 – This is another one Julia and I found on our first cross-country trip, this time in northern Idaho. The larvae mine leaves of arrowleaf ragwort (Senecio triangularis).
41. Phytomyza vancouveriellaEiseman & Lonsdale, 2018 – Although Julia and I found a few leaf mines of this species on the Olympic Peninsula on that same trip, the only known specimens are a few that Mike Palmer reared in Oregon five years later. The host is Vancouveria hexandra, whose common names include “white inside-out flower.”
42. Phytomyza verbenaeEiseman & Lonsdale, 2018 – One last species (for now) from that first road trip; Julia and I found the mines on western vervain (Verbena lasiostachys) in California.
43. Phytomyza ziziae Eiseman & Lonsdale, 2018 – I reared the holotype and some of the paratypes from leaf mines on golden Alexanders (Zizia aurea) I collected while conducting botanical fieldwork in western Massachusetts. Another came from the same Berkshire BioBlitz that produced the type specimens of Phytosciara greylockensis and Platygaster vaccinii. There are also a few specimens that Graham Griffiths reared from heart-leaved golden Alexanders (Zizia aptera) in Alberta in 1973. It’s a bit curious how many agromyzid species are known only from Alberta and Massachusetts…
44. Agromyza arundinariae Eiseman, Lonsdale & Feldman, 2019 – This and the next eight species were described in a paper dedicated to agromyzid flies that Tracy Feldman collected in North Carolina—I helped with rearing and described the leaf mines, and Owen Lonsdale described the adult flies. Agromyza arundinariae is one of three new species Tracy found on the native bamboo Arundinaria tecta.
45. Agromyza indistinctaEiseman, Lonsdale & Feldman, 2019 – I gave this one the name “indistincta” because there was nothing distinctive about it; it’s the fourth species to be reared from seemingly identical mines on grasses in the genus Dichanthelium, and the adult is pretty darn similar to two of the other three.
46. Calycomyza chrysopsidis Eiseman, Lonsdale & Feldman, 2019 – A leafminer of Maryland goldenaster (Asteraceae: Chrysopsis mariana).
47. Cerodontha enigmaEiseman, Lonsdale & Feldman, 2019 – This one is a similar situation to Agromyza distincta; it is a leafminer of Dichanthelium and is an enigma because it is known from a single specimen Tracy collected in his yard. The adult is very similar to Cerodontha angulata, which is the species I’ve reared every time I’ve collected similar mines on Dichanthelium.
48. Cerodontha arundinariellaEiseman, Lonsdale & Feldman, 2019 – The second species reared from leaf mines on Arundinaria tecta.
49. Cerodontha saintandrewsensis Eiseman, Lonsdale & Feldman, 2019 – The third species reared from leaf mines on Arundinaria tecta, named for St. Andrews University, where Tracy works and does much of his collecting (and the only known locality for this species).
50. Liriomyza carphephoriEiseman, Lonsdale & Feldman, 2019 – Tracy first found this species mining leaves of sandywoods chaffhead (Asteraceae: Carphephorus bellidifolius), and I had already decided to name at after this plant when Owen determined that it was the same species Tracy and I had reared from beggarticks (Bidens spp.) in North Carolina, Vermont, and my own front yard in Massachusetts. It’s still a good name for it; several other Liriomyza species mine leaves of Bidens, but this is so far the only leafminer of any kind to be found on Carphephorus.
51. Liriomyza polygalivoraEiseman, Lonsdale & Feldman, 2019 – A leafminer of whorled milkwort (Polygalaceae: Polygala verticillata).
52. Liriomyza triodanidisEiseman, Lonsdale & Feldman, 2019 – A leaf and stem miner of small Venus’ looking-glass (Campanulaceae: Triodanis biflora).
53. Agromyza princei Eiseman & Lonsdale, 2019 – I reared this species from a leaf mine on black raspberry (Rosaceae: Rubus occidentalis) that Julia and I collected in the parking lot of a cemetery in Hartford at the 2016 Connecticut BioBlitz. It is known from a single specimen, which emerged as an adult a year after I collected the larva. When Owen told me he needed a name for this new species, “Raspberry Beret” popped into my head, so I named it after Prince, who had died shortly before we found the leaf mine.
54. Melanagromyza vanderlindeniEiseman & Lonsdale, 2019 – This species is named for John van der Linden, who reared it from dead stems of Joe-Pye weed (Asteraceae: Eutrochium) he collected in Iowa. John has an incredible knack for finding stem-feeding insects that leave little or no external evidence. He has written about some of his natural history discoveries on his blog, and many more can be found on his BugGuide page.
55. Ophiomyia antennariaeEiseman & Lonsdale, 2019 – Julia and I found this leafminer of plantain-leaved pussytoes (Asteraceae: Antennaria plantaginifolia) in beautiful Cane Creek Canyon in northern Alabama in the spring of 2013, shortly after getting in a car wreck in Mobile. The mines are much like those from which Mike Palmer and I have reared O. coniceps in Oklahoma and New England, and Owen and I almost described this new species in our first (2018) paper, but I temporarily convinced him that we should consider the Alabama specimens to be O. coniceps. However, before that paper went to press, Owen reasserted his original position—though he considers one female from Cane Creek Canyon to be a better match for O. coniceps—so we removed the remaining specimens from that paper and dealt with them in the 2019 paper. As it happens, Julia and I had separated out what we thought might be two different mine types on plantain-leaved pussytoes, and that female was the only one that emerged from mines of the type that O. coniceps makes in New England. But Mike has reared O. coniceps from both mine types in Oklahoma, so evidently the difference isn’t entirely consistent.
56. Ophiomyia osmorhizaeEiseman & Lonsdale, 2019 – Another John van der Linden discovery from Iowa; this one is a stem miner of sweet cicely (Apiaceae: Osmorhiza).
57. Calycomyza smallanthiEiseman & Lonsdale, 2019 – In August 2017, Julia and I met up with Noah’s family in Nashville to see the full solar eclipse, and we found this species mining leaves of hairy leafcup (Asteraceae: Smallanthus uvedalius) just around the corner from Noah’s mother’s house.
58. Liriomyza euphorbiellaEiseman & Lonsdale, 2019 – Mike Palmer reared this one from fire-on-the-mountain (Euphorbiaceae: Euphorbia cyathophora) in Oklahoma.
59. Liriomyza garryaeEiseman & Lonsdale, 2019 – Julia and I found this species mining leaves of silktassel (Garryaceae: Garrya spp.) in Arizona and Texas on the way home from checking out the “super bloom” in southern California in 2017.
60. Liriomyza phloxiphagaEiseman & Lonsdale, 2019 – I reared the only known specimen of this species in 2017 from a leaf mine on phlox (Polemoniaceae: Phlox paniculata) in my mother’s garden in Massachusetts.
61. Phytomyza nemophilaeEiseman & Lonsdale, 2019 – Mike Palmer reared this species from leaf mines on Nemophila parviflora (Hydrophyllaceae) in Oregon.
62. Phytomyza salviarumEiseman & Lonsdale, 2019 – Julia and I found this species mining leaves of several different sage species (Lamiaceae: Salvia) on Ann and Bruce Hendrickson’s ranch in Texas in 2017, the same day we collected the holotype of Liriomyza garryae.
63. Grapholita thermopsidisEiseman & Austin (in Eiseman et al. 2020) – A leafminer of goldenbanner (Thermopsis) reared from leaf mines Julia and I collected in Colorado in the yard of our friends Sally Waterhouse and Denny Radabaugh in 2015.
64. Melanagromyza arnoglossi Eiseman & Lonsdale, 2021 – This species, and the twelve that follow, were described in a paper that included John van der Linden, Tracy Feldman, and Mike Palmer as coauthors. Most of the species were found and reared by John, Tracy, or Mike, so I only have my own photos of a few of them. When available, I’ve made the species names link to relevant BugGuide posts. Melanagromyza arnoglossi is a stem borer John reared from Indian plaintain (Arnoglossum) in Iowa.
65. Melanagromyza gentianivora Eiseman & Lonsdale, 2021 – A stem borer John reared from bottle gentian (Gentiana andrewsii) in Iowa; the type series also includes specimens reared by Andrew Williams in Wisconsin.
66. Melanagromyza hieraciiEiseman & Lonsdale, 2021 – A stem borer John reared from rough hawkweed (Hieracium scabrum) in Iowa.
67. Melanagromyza rudbeckiae Eiseman & Lonsdale, 2021 – A stem borer John reared from cutleaf coneflower (Rudbeckia laciniata) in Iowa; the type series also includes specimens reared by Andrew Williams in Wisconsin.
68. Melanagromyza urticae Eiseman & Lonsdale, 2021 – A stem borer John reared from stinging nettle (Urtica dioica) in Iowa.
69. Melanagromyza verbenivora Eiseman & Lonsdale, 2021 – A stem and rachis borer John reared from hoary vervain (Verbena stricta) in Iowa.
70. Ophiomyia nabali Eiseman & Lonsdale, 2021 – A stem miner and petiole borer that John reared from white rattlesnake-root (Nabalus albus) in Iowa.
71. Ophiomyia rugula Eiseman & Lonsdale, 2021 – This is one Tracy reared in North Carolina from short, gall-like leaf mines on groundsel bush (Baccharis halimifolia). The mine looks like a little wrinkle along the midrib, hence the name “rugula,” which is Latin for “a small wrinkle.”
72. Haplopeodes loprestii Eiseman & Lonsdale, 2021 – I reared the two known specimens from a sprig of California fagonbush (Fagonia laevis) that Eric LoPresti gave me. As explained in the linked post, Eric collected the plant sample because it had some leaf-mining moth larvae, and we never actually saw what the fly larvae did but they were presumably also leafminers.
73. Liriomyza euphorbivora Eiseman & Lonsdale, 2021 – A leafminer Mike reared from snow-on-the-mountain (Euphorbia marginata) in Oklahoma.
74. Liriomyza hypopolymnia Eiseman & Lonsdale, 2021 – This is a sneaky one that mines on the lower surface of leafcup (Polymnia canadensis) leaves. There is little or no trace of the mine when viewed from above, and it’s pretty inconspicuous from below too. Julia and I first found the mines in Iowa by MJ Hatfield’s house in 2015, and we found some more in Tennessee in 2017, but they were all empty or aborted in both cases. Luckily, John was able to rear some adults in 2017, and MJ reared some in 2018, so we were able to describe the species from these specimens.
75. Phytomyza flavilonicera Eiseman & Lonsdale, 2021 – This is a honeysuckle leafminer that Mike found in Oklahoma. Like P. sempervirentis, it mainly feeds on Lonicera sempervirens, and its leaf mine is pretty much identical, but the adult has a yellow face (and, of course, different genitalia). It also feeds on L. flava, and the Latin “flavus” (yellow) in its name refers to this as well as the distinctive color of its face.
76. Phytomyza triostevena Eiseman & Lonsdale, 2021 – This is another sneaky one, which John reared from horse gentian (Triosteum) in Iowa. It makes an inconspicuous leaf mine that soon disappears into a lateral vein and then the midrib, and the Latin “vena” (vein) in its name refers to this.
That’s the species tally so far… I guess for completeness I should mention that I’ve also coauthored one genus:
Aspilanta van Nieukerken & Eiseman, 2020 – I helped Erik van Nieukerken with the paper that described this new genus for six moths species that were formerly placed in the genus Antispila. They had originally been placed in that genus because of a similarity in wing pattern, but they turn out to be more closely related to the very different-looking genus Coptodisca. Just to keep things a little confusing, we made the new name an almost-anagram of the old one. I’ve found three of the described Aspilanta species in my yard, and a fourth not far away—mining leaves of grape, Virginia creeper, and sweetfern—and I’ve met the other two on wild hydrangea in Ohio and on canyon grape in Utah. Here’s the type species, Aspilanta oinophylla; it’s the most recently described of the six, named Antispila oinophylla by Erik and Dave Wagner in 2012:
In that same paper, Erik and I also moved the Florida species Antispila eugeniella Busck to Heliozela. Now, “How many species have you renamed?” is a question no one has ever asked me, but just to satisfy my own curiosity, here’s a quick rundown:
In 2019, in the paper where Tadeusz Zatwarnicki and I documented the presence of the European duckweed leafminer Hydrellia albilabris in Maine, we transferred Cavatorella jinpingensis Zhang, Yang & Hayashi to Hydrellia.
In 2020, in addition to the seven changes mentioned above that Erik van Nieukerken and I made, Don Davis and I transferredCameraria affinis and C. leucothorax to the genus Phyllonorycter, and also declared affinis a synonym of P. mariaeella. And we transferred Phyllonorycter arizonella and P. cretaceella to the genus Cameraria. All of these had been placed in the now obsolete genus Lithocolletis (along with many other gracillariids) until Don assigned them to new genera in the 1983 “Hodges” list; for whatever reason he messed up on these four, and I noticed that they were misplaced in the process of putting together my leafminer book.
And this year, Owen Lonsdale and I published a paper that reaffirmed the synonymy of Chromatomyia with Phytomyza, shortly after Michael von Tschirnhaus proposed formally rejecting all of the conclusions of the detailed molecular and morphological study by Winkler et al. (2009) (instead of merely ignoring them, as most Europeans studying Agromyzidae have been doing for the past 12 years). This also involved reaffirming that Napomyza and Ptochomyza should be treated as subgenera of Phytomyza rather than as full genera. So, in addition to explicitly renaming three Chromatomyia species that had never before been placed in Phytomyza, we implicitly renamed well over 100 species back to names that had been used for them before.
So I guess I don’t have an exact count, and the answer depends on what you think of the arguments Owen and I made in the Chromatomyia paper—which, as with all of the papers I’ve coauthored, I’m happy to share with anyone who is interested.
Anyway, thanks once again to all my collaborators and readers, and I look forward to sharing more discoveries with you in the coming year!
Nine years ago this month, I published the first in a series of “monthly mystery” posts in which I wrote about nagging natural history mysteries with the hope that someone out there might have some answers, or at least suggest some possibilities I hadn’t thought of. That first mystery was the identity of these 3 mm long banana-shaped things Noah and I found stuck to pine needles at Yosemite National Park on July 26, 2008:
As I wrote before, “In photos, they look like they could be larvae, but they were hard and stationary and in person they gave the impression of eggs. There were often several in an evenly-spaced row, and all had tips that curved away from the substrate as shown [above].” One reader suggested that they looked like fly pupae, and another thought they might be tasty with lemon juice and cocktail sauce. No further progress was made until today, when I was scouring Middlekauff’s (1958)* publication on pamphiliid sawflies for every available detail about the natural history of the conifer-feeding species. In his notes under Acantholyda zappei, he wrote:
The pale yellow eggs are about 4 mm. long, tapered at each end and crescent-shaped. The shape is most unusual for a sawfly egg and in size may well be the largest known. . . The eggs are deposited singly, their long axis parallel to that of the [pine] needle, on new growth late in June and early July. When the young larvae hatch, they emerge from the end of the egg which tapers least and begin to spin a loose web around themselves, fastening the outer threads to the needles. . .
It had never crossed my mind that a sawfly could produce eggs that big—it seemed like they would have to be from something along the lines of a katydid or a walkingstick. But sure enough, a quick Google search turned up a fantastic photo of an Acantholyda larva hatching from a very similar egg in Finland.
Acantholyda zappei is restricted to the northeastern US and adjacent Canada (which means I should be able to find its eggs in my neck of the woods, though somehow I’ve never seen anything like those Yosemite bananas in the intervening 13 years), but there are 33 other Acantholyda species in the US and Canada, 14 of which occur in California. Some of those can be eliminated as possibilities because they feed on conifers other than pines, but several have never been associated with any host, and none of their eggs have been described, so the exact identity of the Yosemite eggs will remain a mystery for some time. In fact, the only other Acantholyda in North America whose eggs have been described is the “pine false webworm,” A. erythrocephala, which is a European species that was found in Pennsylvania in 1925 and has since spread at least to New Jersey and Ontario (and apparently Alberta). Here are some eggs I found in May 2011 on a white pine needle in Burlington, Vermont that are consistent with that species:
My only other encounter with this genus (that I know of!) is this adult of A. erythrocephala I photographed in Colchester, Vermont in May 2005:
* Middlekauff, Woodrow W. 1958. The North American sawflies of the genera Acantholyda, Cephalcia, and Neurotoma (Hymenoptera, Pamphiliidae). University of California Publications in Entomology 14: 51–174.
I’m finally getting back to working on my guide to sawfly larvae, after a very busy field season followed by several weeks of focusing on writing papers—some of which have involved documenting new host records and previously undescribed sawfly larvae, so in that way I’ve already been making some progress this fall. This week I’ve started to tackle the chapter on conifer-feeding sawflies, and this morning while taking a break from that and sorting through some of my photos from this past June, I coincidentally came across some relevant photos that I couldn’t resist sharing here.
On September 20, 2020, I led one of my only public walks of the year, during which the group encountered some red-headed pine sawfly larvae (Diprionidae: Neodiprion lecontei) chomping on pitch pine needles (Pinaceae: Pinus rigida). I didn’t have any photos of this species yet, so I took three home to photograph them:
They exhibited their charming behavior of standing up and blowing bubbles when disturbed:
Now that I had these larvae I figured I might as well rear them to adults, so I kept them in a jar with some soil in the bottom and two days later they shed their skins…
…and now they were prepupae, done feeding and ready to burrow down and spin cocoons. The prepupa of this species looks much like the feeding-stage larva but its head is no longer red.
Between June 27 and July 5 of this year, three adults emerged from those three cocoons, but as in my previous “Sawfly Surprise” post, they were parasitoids rather than the sawflies I was expecting. Last time the wasps were eulophids, which is the #1 family of parasitoids I get when trying to rear leafminers, but this time they were perilampids. I’ve just encountered perilampids once before, when three adults of Perilampus platigaster emerged from cocoons of braconid wasp larvae that had emerged from some caterpillars that remain unidentified because every last one of them was parasitized. These new perilampids, which Jeong Yoo tells me are P. hyalinus, have the same adorable general appearance as P. platigaster but with the added bonus of being shiny blue and green.
I presume the above wasp is the male, and the one below (more blue, with larger abdomen) is the female.
In my previous Perilampus post I described the life cycle of perilampids that are obligate hyperparasitoids, entering caterpillars with the hope of finding primary parasitoids to parasitize. It turns out that P. hyalinus is sometimes a hyperparasitoid, e.g. emerging from puparia of tachinid flies or cocoons of ichneumon wasps that are formed within the cocoons of Neodiprion sawflies, but normally when it attacks Neodiprion sawflies it feeds as a primary parasitoid. Tripp (1962)* studied this relationship in great detail and reported that P. hyalinus females lay eggs at the bases of pine needles four to six inches away from groups of second-instar Neodiprion larvae. Why? Because it takes the eggs eight to ten days to hatch, and that’s how long it takes the young sawfly larvae to move about four inches along the stem—and there are nine days between molts, so the sawfly larvae will be in their third instar when they arrive near the eggs. Neodiprion larvae that are fourth instar or older cover much more ground and would just blow past the eggs before they hatched. Why not just lay eggs directly on the sawfly larvae? Well, before the eggs hatched the larvae would shed their skins, so that wouldn’t work out. Maybe by now they could have evolved eggs that hatch more quickly, but with the current arrangement they get to avoid that flailing, bubble-blowing behavior shown above. The fluid that comes out of the larva’s mouth is sticky and could cause major problems for a tiny parasitoid that came in contact with it.
So, the P. hyalinus larvae hatch shortly before the arrival of their slow-moving hosts, and they stand erect on the pine needles until the sawfly larvae blunder into them. Each P. hyalinus larva clings to the surface of its host for less than an hour, and then burrows inside and basically does nothing until the following spring. When the weather warms up and the Neodiprion larva starts to prepare to pupate, the P. hyalinus larva pops back out of it and feeds on it externally (but inside the cocoon), quickly paralyzing it and then devouring it over the next two weeks. It then pupates without spinning its own cocoon, and after another two weeks it emerges as an adult and chews its way out of the sawfly’s cocoon.
If I’d had to guess what series of events had led to these little blue-green wasps emerging from the soil into which my sawfly larvae had burrowed nine months earlier, I don’t know what I would have come up with but it certainly wouldn’t have been that! I’m so grateful for everyone who has taken the time to figure these things out and publish them so that curious naturalists, decades or centuries later, are able to find answers in a matter of minutes instead of having to start from scratch.
* Tripp, H. A. 1962. The biology of Perilampus hyalinus Say (Hymenoptera: Perilampidae), a primary parasite of Neodiprion swainei Midd. (Hymenoptera: Diprionidae) in Quebec, with descriptions of the egg and larval stages. The Canadian Entomologist 94: 1250-1270.
Although most of what used to be my lawn is now an untamed meadow interspersed with gardens, fruit trees, and berry bushes, once a month or so I do break out the ol’ battery-powered lawnmower to maintain a network of trails through it all. On June 11, which was one of those rare occasions, I paused my mowing and flipped over the mower to scrape out the wads of vegetation that were starting to choke up the blades. I was surprised to find a fly puparium, which I at first interpreted to have been something I had run over with the mower that had miraculously made it past the spinning blades intact.
When I found a second one just like it, I realized that these were puparia from larvae that had developed in the decomposing vegetation that I had failed to scrape off the mower after I had finished my previous mowing session. They looked similar to Anthomyiidae puparia—some anthomyiids are leafminers, but others feed on a variety of other things including decomposing vegetation—but they could have belonged to some other related family.
As I continued to dig through that crud, I found this bristly thing, which I believe to be the puparium of a lesser house fly (Fanniidae: Fannia canicularis)…
…as well as a bunch of larvae like this one:
The fact that this larva has a distinct little head capsule tells us that it’s not one of the so-called “higher” flies, like anthomyiids and fanniids, that form puparia (i.e., they pupate inside the hardened skin of the larva, which the adult ultimately escapes by inflating a big balloon from its face). It’s something more along the lines of a midge or crane fly that forms a naked, exposed pupa.
Naturally, I stuffed a chunk of this rotting plant matter, including these larvae and puparia, into a vial to see what they would all turn into. When I checked the vial on June 23 I found about a zillion of these inside:
This is Coboldia fuscipes, a member of the family Scatopsidae, which are known as the “black scavenger flies.” It belongs to the same group of “lower” flies (Bibionomorpha) as the gall midges, fungus gnats, March flies, and wood gnats, and it is the adult that goes with the larva in the previous photo. Nothing ever emerged from the puparia in the first two photos, but it turned out there was a third species of puparium-forming fly in the mix. Two females of Drosophila busckii (Drosophilidae) emerged, also on June 23, and I was able to find one of their empty puparia.
So, not quite the 30+ species of arthropods I found in a cubic foot of my lawn, but I think four species of flies in a handful of decomposing lawn isn’t too shabby either!
Thanks to Brad Sinclair for identifying the adult flies.
At the moment there are 648 observations on iNaturalist purporting to show the “oak shothole leafminer” (Agromyzidae: Japanagromyza viridula). Apparently I have personally verified 93 of them, in almost all cases based on the presence of leaf mines. Virtually all the rest are just photos of holes in oak leaves, many of which probably were made by this fly, but in most cases there is no way to tell for sure. I wrote about this species last year, and for your convenience I’ll copy and paste the relevant portion here:
This fly is called the “oak shothole leafminer” because of the holes that open up in the leaves as a result of feeding by adult females. They use their ovipositors to stab the young leaf and then turn around to drink the juices from the wounds. As the leaf continues to expand, a hole opens around a tiny necrotic disc that forms around each puncture (upper right in the photo below). Holes also open up around eggs that are inserted in the leaf (lower left).
In this closer crop you can see the tiny white (because it’s backlit) puncture from the ovipositor near the right edge of the necrotic disc.
There are often multiple holes per leaf. Eventually the necrotic discs drop out, leaving just the “shotholes” as evidence.
Japanagromyzaviridula seems to have just one generation per year, but unlike most agromyzid flies with this type of life cycle, adults emerge within a few weeks after the larvae exit their mines, rather than the following spring.
So, just to be clear, these holes do open at the beginnings of leaf mines of this species (as in the left side of the first photo above), but most of the holes are just caused by the females stabbing the leaves and they have nothing to do with leaf mines. I’ve done my best to discourage folks from adding pictures of holes in leaves without any associated leaf mines to my iNaturalist “Leafminers of North America” project, and early on I left comments pointing out that these holes can be made by other things, but I gave up due to the sheer volume, so take that distribution map with a grain of salt!
Anyway, back on May 25 I noticed this holey leaf on one of the little red oak saplings I haven’t had the heart to mow in the unkempt meadow that is my yard:
If I posted this photo to iNaturalist, it would probably become elevated to a “Research Grade” observation of Japanagromyza viridula within minutes. The thing is, though, when I flipped the leaf over, I found that all of the holes had been made by three little sawfly larvae:
These oak-feeding sawfly larvae with forked spines belong the the genus Periclista (Tenthredinidae). This is the first time I’ve ever seen them in my yard and I don’t know if there’s any way to tell what species they are without rearing them to adults, which don’t emerge until the following spring. So far I’ve reared three different species from oak elsewhere in Massachusetts, and the larvae did show some differences in the head pattern; if those differences are significant, then the ones in my yard might be P. albicollis, which looks like this as an adult:
(Incidentally, when I tried uploading the photo of the holey leaf to iNaturalist just now, the machine learning auto-ID feature told me it was “pretty sure” my photo depicted the work of some kind of chrysomelid leaf beetle; all of its “top suggestions” were likewise leaf beetles and it made no mention of agromyzid flies. Still wrong, but at least it doesn’t think all holes in oak leaves indicate “oak shothole leafminer” as some human observers do. Is my Tracks & Sign of Insects book partly to blame for this perception? Probably.)
I’d be remiss if I didn’t mention that the first photo of the sawfly larvae above also shows galls caused by an undescribed species of midge in the genus Contarinia (Cecidomyiidae), another thing I hadn’t found in my yard before. Just let the squirrels and blue jays plant a few acorns in your yard and your local biodiversity will skyrocket! Another leaf on that same sapling had some different sawfly larvae (Pergidae: Acordulecera) munching on the edge of it.
No way to put a species name on those even if I did rear them to adults; they would pretty likely turn out to be something in the Acordulecera dorsalis complex, which no one has yet tried to sort out. We know so little about some of the most common bugs around us.
It’s been just over four months since I last posted here, and I’ve got a few updates to share.
First of all, I’m alive and well; it’s just been an extremely busy field season! In contrast with last year, when I was minimally employed for a good chunk of the time and got to devote many hours to chronicling the goings-on in my yard, this year I’ve been working nonstop in various places that were mostly 1-2 hours from home. Things have finally slowed down in the past couple of weeks, and soon I’ll start going through all my photos from the past half a year and posting the highlights here.
Second, I just finished putting together my fourth annual Leafminers of North America calendar, and as with last year, I will send a copy to anyone who makes a donation of at least $30 (the amount WordPress charges me each year to keep this blog free of annoying ads) before the end of November, which you can do here (select “Send,” and then include your mailing address in the notes). This year each month shows a whole leafminer life cycle instead of a single full-page photo per month.
Third, today the much-anticipated July issue of Proceedings of the Entomological Society of Washington was finally published, and it includes a short paper of mine* that relates to two things I’ve written about here previously. In June 2018, I wrote about two lauxaniid flies in the genus Minettia I had recently met that seemed very interested in leaves that were being mined by other flies. In my concluding paragraph I wrote, “It’s tempting to think these flies are laying eggs on or in the leaf mines and their larvae will develop as secondary invaders in the mines, maybe after the original miners have left.” In June 2019, when I announced the completion of the first edition of Leafminers of North America, I mentioned that I had just been on a successful mission to collect more larvae of a Calycomyza species that appears only in early June, has only been found at a single location, and is so far known only from unidentifiable females, but almost certainly represents a new species. Well, I did manage to rear some more adults of that Calycomyza, including a single male (which Owen Lonsdale hasn’t yet had a chance to examine), but a couple of weeks after the last Calycomyza larva had exited its mine and pupated, a different kind of fly larva emerged from one of the now decomposing leaves:
I didn’t get around to photographing this larva’s puparium until the following spring (which is to say, spring of 2020), when the adult fly emerged:
Under magnification, I could see that the puparium was covered with the calcareous secretion that lauxaniid puparia have been described as having, and the adult proved to be a Minettia, the same genus I had suspected of sometimes developing in abandoned mines of other flies!
One of my manuscript’s reviewers, at least, thought that was pretty exciting.
And finally, although I haven’t had time to write any BugTracks posts in recent memory, I have been faithfully posting a photo of a different species from my yard on Twitter every day since October 14, 2020. If you’re so inclined, I think you can scroll through those photos whether or not you have a Twitter account. The first 250 are here, the second batch is here, and I recently started a third thread after the first year was up. In other spare moments while at my computer, I’ve been making my way through the backlog of observations in the “Leafminers of North America” iNaturalist project, where I’m currently up to August 3, with 7360 observations left to go. I’ve been sharing some highlights in another Twitter thread.
That’s all for now, but more coming (relatively) soon!
* Eiseman, Charles S. 2021. Minettia Robineau-Desvoidy spp. (Diptera: Lauxaniidae) as secondary invaders in leaf mines of other insects. Proceedings of the Entomological Society of Washington 123(3): 669–672.
Two years and two weeks ago, I announced the completion of the first edition of my Leafminers of North America e-book.
It’s been gratifying to see more and more people all across North America looking for leaf mines, successfully using the keys in my book to identify what they’ve found, and documenting new host and distribution records as well as previously unknown mines in the iNaturalist project I created.
But some of the most enthusiastic leaf mine hunters don’t have my book, and I have no doubt that the $90 price is a barrier to some. So I’ve decided to make the first edition available on a sliding scale. To get access to the full first edition, all you have to do is use this link to send a payment of any amount ($5 or more), entering “leafminer book” in the “Add a note” field, along with the email address where you’d like to receive the link.
Or you can become a patron at $5 a month, and you’ll get the whole first edition right away as well as start receiving the second edition in monthly installments.
Anyone who contributes (or has already contributed) $90, either all at once or cumulatively, gets a lifetime subscription to updates. I’m about halfway through releasing the second edition, and the portion I’ve done is already more than 200 pages longer than the corresponding portion of the first edition. In addition to new host and distribution records and previously unknown mines, I’ve been adding photos of adults and mines for species that weren’t illustrated previously; names of newly described species; new natural history information from recently published papers; and other new observations that haven’t yet been reported in peer-reviewed literature.
The new discoveries are showing no sign of slowing down, so I expect to start in on the third edition soon after I finish the second. The latest came the day before yesterday: while conducting a botanical inventory in Southborough, MA, I spotted a leaf mine on a young grapevine that I recognized right away as something never before documented on grape.
Here’s the same mine a few hours later, after I got it home and had access to a better camera:
Everything about this mine, including the two yellow larvae feeding side by side, is consistent with Orchestomerus eisemani, heretofore known as a Virginia creeper specialist. Adults of the other eastern Orchestomerus species, O. marionis, have been collected on grape, but if that species were a leafminer I would think someone would have noticed its mines before now. I’m betting this is O. eisemani trying out a new host, a hunch supported by the presence of several vacated mines on Virginia creeper a few meters away—which, incidentally, is the first evidence of this species in Worcester County, a slight extension of its known range. It’s the next county over from my own, albeit way over at the other end. I wonder how long I’ll have to wait to see O. eisemani in my own yard.
Yesterday morning the larvae had extended their mine considerably, still feeding side by side…
…and overnight they popped out and burrowed into the soil at the bottom of the jar I had placed the leaf in. With any luck, they’ll emerge as adults in a few weeks and I’ll be able to confirm their identity.
I may or may not get around to reporting the result here, but you can be sure it will make an appearance in the third edition of Leafminers of North America!
This morning I had a look around my yard after being away for the past week, and I met this fantastic creature on a leaf of one of our cultivated hazelnuts:
Its body was awkwardly contorted, and it took me a lot of tries to get a photo with all (or most) of it in focus.
When it started walking around, I was surprised to see that it was able to unfurl those tendril-like appendages (even harder to get in focus when it was in motion, but these photos will give you some idea).
This strange beast is a horned spanworm (Geometridae: Nematocampa resistaria), something I’ve encountered only a couple of times before, and this one was the largest and fanciest. Here’s a very young one I found on a black cherry leaf on 6/13/2013:
And one found on a woodland sunflower, 6/8/2019:
Although today’s larva was the first I’d seen in my yard, I spotted an adult of this species on the basement ceiling on 7/6/2014:
The caterpillar seems like something that belongs in the tropics, and sure enough, here’s a video showing a Nematocampa larva in action in a Peruvian rainforest:
Adults have emerged from another 20 or so overwintered vials and jars since my previous post. Here are some more that came from larvae collected right in my yard.
On June 21, I collected these larvae from one of our cultivated hazelnuts (Sawfly #27 in this post):
Thirteen of them reached maturity and burrowed into a jar of soil by the end of the month. Over the past few days, three of these wasps have emerged from the soil:
They appear to be braconids in the genus Ichneutes (thanks to Gergely Várkonyi for the ID). In my decade of rearing all sorts of herbivorous insects, to my knowledge I have only previously reared two braconids in the subfamily Ichneutinae, both from tiny leaf-mining moths. The ichneutines that parasitize sawfly larvae oviposit in their hosts’ eggs, or sometimes in young larvae, but their offspring wait until the sawfly larvae have finished feeding and spun their cocoons before doing most of their own feeding and ultimately killing their hosts. Did the mother Ichneutes manage to insert an egg into every one of these hazelnut larvae (or the eggs from which they hatched) before I got to them? Time will tell.
Last year’s Leafminer #89 was Stigmella prunifoliella (Nepticulidae), which I identified based on a predated leaf mine on black cherry that I found on June 26. On September 28 I collected a few leaf mines on peach that I presumed were the work of this species, but I wanted to make sure since it hadn’t been documented on peach before. Here is a very early mine, with the green larva munching away inside…
…and here is a vacated mine three days later…
…and here is the adult that emerged on March 22:
Virtually all of the insects I have emerging right now are univoltine species, with just one generation per year, and larvae found only in spring or early summer. With the exception of some parasitoid wasps, Stigmella prunifoliella is the only multivoltine species that has made an appearance so far.
Last year’s Sawfly #25 was a larva I found in June on white avens (Rosaceae: Geum canadense)…
…and within a few days I found larvae that I thought might be the same (though I noted a behavioral difference), feeding on leaves of cultivated strawberries.
On March 22, an adult emerged from each jar—strawberry…
I still think they might be the same! I believe the only sawfly in North America with free-living larvae that have been found on avens is Pristiphora pallidiventris, and this clearly isn’t that. I’m guessing this is one of the six species of Allantus, Empria, and Taxonus that are known to feed on strawberry, but I won’t worry about which species that might be just yet. [Edit, 3/26/2021: Marko Prous says these are “Empria (maculata maybe, which seems to be a complex of several species)”.]
Early last June I pointed out a gall on a fox grape leaf made by Heliozela aesella (Heliozelidae), an odd species in a family that (in North America, anyway) is otherwise composed of leafminers. Here is a better look at one of the galls, viewed from above and below:
The mature larva cuts out an oval chunk from the upper surface of the gall and wraps it around a tube of frass held together with silk, then wanders off, dragging this portable burrito-house until it finds a suitable place to overwinter, at which point the gall chunk becomes its cocoon.
On March 22 two of these emerged as adults:
While I was putting together my “Bugs in Winter” course, I cut open some goldenrod stem galls from my yard so I could include photos of their interiors in one of my slideshows. When I cut open this gall of Epiblema scudderiana (Tortricidae) in January…
…I found the live moth larva still inside (as would be expected for this species), visible in the photo below through a little nick in its protective silken tube.
Since it would likely be doomed if I put the opened gall back outside, I instead put the gall in the fridge along with the other overwintering bugs, and took it back out with the rest of them on March 1. Alas, it turned out the larva had already been doomed by parasitoid larvae living inside it: eleven of these microgastrine braconid wasps emerged on March 22:
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