© Steven J. Cary, December 23, 2024
In my last post of 2024, I’m putting back out to you my happy story about Ellis’ Blue, which accidentally snuck its way into publication back in late October, before it was ready. PEEC helped me unpublish quickly, but a few of you were quicker, saw it, and then maybe watched it disappear. Blog-o-magic! Well, now it’s back for good, a bit improved, or so I hope.
But first, please note that Lisa Tannenbaum has a recent butterfly-rich blog post here: San Lorenzo Canyon. And mid-December reporting by Marta Reese and Jim Von Loh confirms that butterflies continue to fly along our southern border, when weather permits. Granted, it’s mostly the usual suspects, but how choosy can we be this time of year?
No Blues for Ellis’ Blue: Discovery a colony of Ellis’ Blue (Euphilotes ellisii) and posting to iNaturalist shows how to nail down the rest of our mysterious dotted-blues (Euphilotes spp.), by Steve Cary. Ellis’ Blue [Euphilotes ellisii (Shields 1975)] was discovered and described from southwestern Colorado fifty years ago. There have been several documented, confident sightings, of Euphilotes ellisii ellisii in northwest NM (we have the nominate subspecies). Its larval host is known to be Crispleaf Buckwheat (Eriogonum corymbosum). thus, when seeking Ellis’ Blue it is possible to go into the field with an idea of where and when to look and what to look for in terms of hostplants, behaviors and wing characters. So, what’s the problem?
Well, first, I am not a botanist and there are 250 confusing species of buckwheats; which one is corymbosum? Second, there are several species of dotted-blues that all look about the same and fly in the same region/habitat at about the same time of year; their distinguishing marks can overlap with each other and be . . . not distinct. It is not difficult to go out in August and find a good buckwheat patch with dotted-blues cavorting about. But my lazy habit of snapping a variety of easy ventral photos, no matter how fine, simply does not provide enough information to confidently distinguish the dotted blues. If that’s the problem, then what is the solution?
I think the solution revealed itself this last August on the citizen science internet platform known as iNaturalist, without which it probably would not have happened. In August 2022, naturalist Christopher Rustay was in the field near Torreon in western Sandoval County, where he photographed a butterfly and a wild buckwheat; he submitted his images to iNaturalist (obs. 133087065, see below). You can see this and other observations discussed in this story by going to iNaturalist, click “Explore” then specify Ellis’ Blue; the “where” is Sandoval County, NM. After you remove all filters and deactivate “needs ID,” you can zoom in to see the cluster of observations in the vicinity of the community of Torreon. You can repeat that process for Crispleaf Buckwheat.]
Christopher had included two pics of the butterfly showing the underside. He suggested via iNat that it might be Lupine or Acmon Blue, but having never knowingly seen a dotted-blue (Euphilotes sp.) he was confident only that it was a blue of some kind. His observation languished for almost a year, but in July 2023, Joshua C’deBaca noted the lack of shiny blue scintillae in the black dots next to the orange hindwing band and identified it as a dotted-blue (genus Euphilotes). Then it caught my eye because I continually troll iNat for dotted-blue sightings. Christopher’s second image showed a probable oviposition on the buckwheat, and for me that pretty much sealed the deal that this was a Euphilotes, or dotted-blue. Adding my two cents to the iNat sighting (part of the fun), I suggested it might be difficult to make a confident ID to species using only the two underside images that Chistopher had uploaded to iNat. From those images alone, it could be Euphilotes centralis, E. rita coloradensis, E. ellisii or even E. pallescens. Getting more butterfly images, especially topside views, and getting the plant IDed would go a long way toward getting a species-level identification for the butterfly.
Upon passage of another year, in early August 2024, Joshua and Mike Shoop inquired with me about tracking down some of my old Euphilotes records from Sandoval County. I made some specific suggestions of what to look for and where, but I also suggested they investigate the place near Torreon where Chistopher had been back in August 2022. They located that spot on iNat, went there, and Mike S. emailed me as follows on August 16: “We found a very large stand of E. corymbosum (both Joshua and I felt confident on the species) we found . . . Euphilotes on the corymbosum that looked more like Ellisii. . . . An added benefit was Mormon Metalmarks that were nectaring there, a life butterfly for Joshua.” Mike S. put some additional underside images on iNaturalist (obs. 236174827 and others). [Mormon Metalmarks use a variety of Eriogonum spp. as hosts.]
Considering the images above . . . the orange band on the female’s dorsal hindwing looks pretty narrow and too petite to be E. rita coloradensis, so I started thinking perhaps it was Ellis’ Blue. But Mike’s photo below showing the extra orange on the ventral forewing doesn’t really match anything; perhaps Spalding’s Blue, but that has only one host buckwheat and this site did not have it. Plus, the faint dark marks on the hindwing suggested maybe Pallid Blue (E. pallescens). It was kind of a muddled start to getting this butterfly identified, but the story developed organically from there.
I was sufficiently curious that I went to the site myself on 8/22/24, using iNat to navigate to the location, with a goal of getting a full dorsal view, male or female. I arrived early in the day because the morning warm-up is often when they do a lot dorsal basking. But the morning proved to be a bit cloudy and the warm-up was not proceeding according to my schedule. After two frustrating hours of 3-4 butterflies coyly showing undersides only, a male finally decided to reveal what he had (see my photo below). Based on the compact pink/orange aurora at the hindwing anal angle, and moderately checkered forewing fringes, I had more confidence it was Ellis’ Blue.
Unbeknownst to me, or perhaps anyone else, Mike Andersen was also watching iNat for posts regarding this site and he showed up the very next day. He then posted to iNat a huge raft of terrific images he had taken of the blues at that site. Mike A. reported to me as follows: “I got on to the Torreon colony because Chris Rustay and Mike Shoop posted iNat records from 28 Aug 2022 and 16 Aug 2024, respectively. Truth is, I have tried to find your locality “6 miles west of San Ysidro Pueblo on Hwy 550” without luck the past couple of years, so it was welcome news that Torreon materialized as an easy spot for ellisii.” If you want to know what this butterfly looks like, male and female, dorsal and ventral, and how it behaves, courts, mates and oviposits, you need look no farther than Mike A’s rich hi-res images on iNat.
[If you’ll permit me a brief sidebar, the new way of describing a site using lat/long with enough resolution to pick out a gnat’s eyebrow, is orders of magnitude better that what we did only 20 years ago, especially in a landscape without lot of named landmarks or intersections. At that time, “6 miles west of San Ysidro Pueblo on Hwy 550” did not seem all that bad. Sure, there was slop in that system; where did San Ysidro Pueblo start/stop? How accurate was my odometer? One might have to do some recon before maybe relocating that buckwheat stand, and those stands do change over time, but there was no other way to do things. That recon itself was half the fun anyway because who knew what else you might find while whacking bushes along the way? Things change, and mostly for good, but the “old days” seemed good at the time, too. At least the highway was paved and I had a vehicle with a working odometer!
Christopher also caught wind of the new activity at that site, so two years after his initial post he back-tracked to the buckwheat sighting he submitted to iNat back in August 2022. As luck would have it, in December of that year, a professional botanist reviewed Christopher’s observation with photo (buckwheat: obs. 132750518) and identified it as Crispleaf Buckwheat (Eriogonum corymbosum). Thus, all plant IDs pointed firmly at Crispleaf Buckwheat, closing that loop as well.
It took a couple of years for the evidence to accumulate and the story to ripen to what I think is a firm conclusion about the plant and the butterfly. That may seem like a long time but considering that it was done only with photos and iNat submittals, I consider that a terrific accomplishment. Heck, we now know how Ellis’ Blue actually looks in northwest New Mexico! That is significant and it was a community effort!
Thinking larger, we may now have a formula for getting similar outcomes for other buckwheat patches and their dotted-blue colonists. These are the steps: 1. Identify a robust and accessible patch of a wild buckwheat that hosts a dotted-blue. 2. Get the buckwheat identified as confidently as possible; qualified botanist highly recommended. 3. Photo-document the details of the dotted-blue, including clear views of male and female, dorsal and ventral, of multiple individuals; document oviposition on the plant and nectaring habits. 4. Share these observations on a public citizen science platform so others can benefit, learn and contribute to the effort
After consultation with a couple people more experienced than I with Euphilotes blues in the Four Corners region, I am adding two more steps, with explanations:
5. Collect a small number of individuals (e.g., 2 males, 2 females). Laboratory analyses (dissection and DNA) will provide the decisive evidence of what any colony of Euphilotes actually is. I agree with Andy Warren that we need to have that capability in our tool bag. [Thanks, Andy.] and a recent exchange of emails with Simon Doneski, a graduate student at UNM’s Museum of Southwest Biology, indicates he is eager to do just that. Then one more thing . . .
6. Photograph larvae. A recent email from Utah butterfly rearer Todd Stout [Thanks, Todd.] reminded me that the various buckwheats discussed above can and do occur together, which can further complicate the issue of which dotted blue (or blues) you may be looking at. In such a situation, Todd notes as follows: If plants belonging to Eriogonum species B grow sparsely among a thick stand of Eriogonum species A, each being a known host plant for a particular dotted-blue species, females looking to place eggs on Eriogonum A may inadvertently place an egg or two on Eriogonum B; and vice versa. Larvae usually develop normally on each. Thus, Crispleaf Buckwheat can in some circumstances also have larvae of Pallid Blue (Euphilotes pallescens), basically by accident. You might have a nice stand of crispleaf buckwheat and conclude you have Ellis’ Blue, and you probably do, BUT . . . per Todd . . . why not add another layer of evidence? Fourth instar larvae of E. ellisii and E. pallescens are distinctly different. Tracking them down on the host plant is not particularly difficult. Todd says to visit the buckwheat patch about a month after peak adult Euphilotes flight (that would be mid-September in most of NM). Place a white cloth under some inflorescences, vigorously shake or knock with a stick, until larvae fall onto the cloth, then obtain photos (or specimens). His graphic below shows how to differentiate ellisi larvae from pallescens larvae.
Whether or not that situation applies to the Torreon site or any site, it is good practice for us observers to go back and check larvae – it’s an opportunity to gather another bit of evidence that can further seal the deal of dotted-blue identification, a goal for which one can never have too much information. For the Torreon colony this task will have to wait until next year, but hey, we can do it!
Given the vagaries of life, work, weather, climate, busy schedules, etc., this 6-step program may take a couple of years to play out for naturalists working any particular stand of buckwheats, as it did for the Torreon colony. That’s more than OK. We’ve been waiting decades, so another year here and there is not a concern. We have to think long term. I particularly recommend we target: (1) additional stands of E. corymbosum to define the appearance and geographic distribution of Ellis’ Blue in NW NM; (2) stands of E. leptocladon to further define the appearance and distribution of Pallid Blue (Euphilotes pallescens) in NW NM; and (3) stands of E. effusum to further define the appearance and distribution of ‘Colorado’ Rita Blue in NW NM.
That’s a lot of stuff, but it’s manageable and conceivable for a community of lepidopterists working in collaboration over a number of years. Begin with one site, then recruit one or more friends/colleagues to get in on the fun. That was the secret sauce for the Torreon Ellis’ Blue colony. It involved five of us, plus a helpful botanist. After you’ve studied it for 2 or more years, it’s OK move on to the next one.
Finally, Jim Brock recommends that if you are working a patch of crispleaf buckwheat (Eriogonum corymbosum) for Ellis’ Blues or Mormon Metalmarks in late summer, you also might go back in spring and look them over for a greenie: Callophrys sheridanii paradoxa. That would be a terrific catch and a new butterfly for New Mexico!
Muchas gracias for a wonderful 2024. Happy Holidays! Feliz Navidad! Prospero Año Nuevo! See you next year!