matthias22's Journal

April 4, 2026

An unrecognized species of Astragalus from northern New Mexico mountains


Image: The Angel Fire milkvetch observed by Christopher Rustay (@christopherrustay) near Angel Fire, New Mexico, see https://www.inaturalist.org/observations/170036635. This represents the second observation of this species on iNaturalist and the first that shows the flowers (reproduced under license CC BY-NC 4.0, https://creativecommons.org/licenses/by-nc/4.0/, © Christopher Rustay).

The purpose of this journal post is to draw attention to an unrecognized species of Astragalus in the Sangre de Christo Mountains at the southern end of the Rocky Mountains of New Mexico.

History of discovery. I first came across this species on iNaturalist in 2022 when I was identifying milkvetches from New Mexico. I was unable to identify it at the time and left it at genus level: https://www.inaturalist.org/observations/170545709. I revisited this observation a year later and decided that it was A. robbinsii. Around the same time, I came across another observation which I identified as A. flexuosus: https://www.inaturalist.org/observations/172630938. At the time I did not connect the two observations, but now I believe they show the same species. Then, after a two-year hiatus, two additional observations came to my attention in October 2025: https://www.inaturalist.org/observations/284718562, https://www.inaturalist.org/observations/295553656. Again, I did not connect the to the previous observations or to each other and identified one of them as A. bodinii and the other as A. multiflorus. I should add that all four species have been documented from this area of New Mexico. Of these four observations only the one I identified as multiflorus had pods, but they are not captured very well and are hidden in a tangle of foliage. Recently, I discovered another seven observations, including one that shows the pods quite well (https://www.inaturalist.org/observations/300082093). At this point, I finally realized that all these observations show the same species which bears features of the four species I had identified it as before, but actually matches none of them.

Observations. Here is a complete list of the observations I found, sorted by geographic area. I believe that this is all there is at the moment on iNaturalist since I also went through unidentified observations of Fabaceae and checked observations of other genera that look similar (e.g., one was initially misidentified as Vicia). All observations are from four localities in Taos and Colfax Cos. at elevations from 2,400-2,800 m (7,900-9,200 ft) (asterisks denote observations with pods):

Taos County
Agua Sarca Canyon, Cibola National Forest:

Valle Escondido:

Colfax County
Angel Fire:

Cimarron Canyon State Park, Clear Creek Trail:

Since I don't know what species it is I am going to nickname it the 'Angel Fire milkvetch' after one of the localities (and because it has a nice ring to it). Below are diagnoses which differentiates it from the four species it resembles:

Astragalus robbinsii

  • pods flattened, not stipitate, seemingly glabrous (vs. somewhat 3-sided, stipitate, with black pubescence in robbinsii)
  • wing petals wide distally not curved around their long axes (vs. narrow distally, often curved like the halves of a cylinder)
  • dorsal calyx teeth not shifted ventrally and not much farther apart than each one is from the lateral calyx teeth (vs. shifted ventrally, usually widely separated and much closer to lateral teeth)
  • leaflets often much longer than wide and elliptic (sometimes wider below the middle), usually with pointed tips (vs. usually wide, with rounded tips)

Astragalus multiflorus

  • pods similar (i.e., flattened) but lacking stipes (present in multiflorus). NB: one observation shows dark brown pods (https://www.inaturalist.org/observations/53761075) which usually happens in fully mature multiflorus pods
  • corolla often lavender, including banner (vs. usually white, rarely banner partly lavender)
  • racemes much longer than subtending leaves (vs. about as long)
  • leaflets wide, elliptic to lanceolate (vs. usually linear, narrow)
  • stems few, sometimes long, growth form not shrubby (vs. stems often numerous and usually shorther, resulting in a shrubby look
  • growing in ± shaded, montane forest or montane meadows (vs. usually ± open, sparsely vegetated sites such as eroded hillsides in NM)

Astragalus flexuosus

  • pods flattened, elliptic, not freckled (vs. usually ± cylindrical in flexuosus, often freckled in NM populations, e.g. compare to https://www.inaturalist.org/observations/168719076 from Bernalillo Co., at 2,300 m or 7,550 ft)
  • calyx pale green, often with sparse black pubescence, teeth long (vs. often purplish, with teeth almost always short)
  • leaflets wide, elliptic to lanceolate, with pointed apex (vs. usually narrow and parallel-sided, if wide then with apex obtuse to truncate or retuse) NB: This species is highly variable. All three described varieties (flexuosus, diehlii, greenei) occur in New Mexico. I have limited familiarity with var. diehlii and greenei.

Astragalus bodinii

  • pods flattened, elliptic, seemingly glabrous (vs. somewhat 3-sided, swollen, slightly bladdery, sometimes slightly curved, strigose in bodinii)
  • corolla largely whitish or lavender, with a purplish keel (vs. largely purple)
  • stems few, ascending to sometimes tall and completely erect (vs. usually numerous, spreading or prostrate, usually mat-forming)

Conclusions. Based on the mentioned characteristics, I feel confident in ruling all mentioned sympatric species except flexuosus. A search on SEINet for flexuosus from Taos and Colfax Cos. did not yield any herbarium specimens that appear to be the same species (none exist from the same localities, except one from Angel Fire, which looks like a typical flexuosus). The Angel Fire milkvetch does neither resemble flexuosus from lower elevation in northern New Mexico, nor flexuosus from mountains farther north in Colorado or farther south in New Mexico. It appears to be a distinct population, that might be an unrecognized variety of flexuosus or an unrecognized species. The strongly flattened pods are very much unlike flexuosus. Therefore I am leaning towards the latter hypothesis.

Acknowledgements. I would like to thank the nine observers who contributed these interesting obervations: @maryadams (3 obs.), @jeffpennington (2 obs.), @andrewhagglund, @bvking98, @christopherrustay, @clairegentry, @eschmitt505, @kevinfloyd and @lexhersh. If you regularly make observations in this area please keep your eyes open for this species. It would be especially helpful to have additional high quality images of the pods of this species. Thanks!

Posted on April 4, 2026 12:24 AM by matthias22 | 3 comments | Leave a comment

October 3, 2025

A new Astragalus from the Kobuk Dunes in Alaska?


Fig. 1: Astragalus sp. from Kobuk Valley National Park, observed by @kilasiak (see https://www.inaturalist.org/observations/29122961, CC license https://creativecommons.org/licenses/by-nc/4.0/)

This journal post is about five observations of Astragalus from the Great Kobuk Sand Dunes, which are part of Kobuk Valley National Park in Alaska (official website: https://www.nps.gov/kova/learn/nature/great-kobuk-sand-dunes.htm):
https://www.inaturalist.org/observations/15047948 (observed by @westernarcticnps)
https://www.inaturalist.org/observations/29122961 (observed by @kilasiak)
https://www.inaturalist.org/observations/304616879 (observed by @popojo)
https://www.inaturalist.org/observations/176971074 (observed by @cjhmiller)
https://www.inaturalist.org/observations/301667982 (observed by @kgofrdgmailcom)

1) The story begins with an oddball observation of an Astragalus from the Kobuk Dunes which I first noticed in March 2023: https://www.inaturalist.org/observations/15047948. It was made by Western Arctic Park Rangers (@westernarcticnps) and includes a single image of a vegetative plant without flowers or fruits. The observation was sitting at the family level, and I identified it as genus Astragalus because it shows the typical habitus of an Astragalus, i.e. it had pinnate leaves and well-developed stems. The plant is conspicuously grey-pubescent and thus resembles Astragalus australis, a widespread species that is fairly common in Alaska and sometimes grows on sand, especially along rivers. However, the leaflets were much wider than in that species so I left the ID at genus level and added "Australis?" in the comments field.

2) On September 29, 2025, I received an automatic notification from iNaturalist about two discordant identifications of this observation as Oxytropis kobukensis. The latter is a stunningly beautiful species of Oxytropis that appears to be endemic to the Kobuk Dunes: https://www.inaturalist.org/taxa/166014-Oxytropis-kobukensis. In order to clarify the identification of the species, I looked for similar observations from the dunes and discovered another observation that was also misidentified as O. kobukenis (https://www.inaturalist.org/observations/176971074, see Fig. 2). This observation by Celia Miller (@cjhmiller) had four images and was much more informative since it shows the deflexed, 3-sided pods of this species. The identification as O. kobukensis was obviously incorrect because the latter has erect, grooved pods and is acualescent.


Fig. 2: Astragalus sp. from Northwest Arctic Borough, observed by Celia Miller (see https://www.inaturalist.org/observations/176971074, CC license https://creativecommons.org/licenses/by-nc/4.0/)

3) In the following discussion, Mihail Knjasev (@mihail13) and Aaron Liston (@aaronliston) suggested that the species was indeed an Oxytropis (other than kobukensis), based on the slightly asymmetrical leaves. Mihail suggested Oxytropis deflexa var. dezhnevii Jurtz. as a possible alternative. The latter is an eastern Eurasian taxon that has never been recorded from North America (see https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:952734-1). I maintained that it had to be an Astragalus because of notable differences in fruit morphology (for detailed arguments see the observation: https://www.inaturalist.org/observations/176971074). Community consensus then started to shift towards Astragalus.

4) The Astragalus hypothesis gained further support when Mihail discovered another observation from the same area that was also misidentified as Oxytopis kobukensis: https://www.inaturalist.org/observations/304616879 (see Fig. 3). This observation only has one image but it revealed a new intriguing detail, i.e. that at least some of the pods have a well-developed stipe (the pods in Celia Miller's observation appeared sessile, see Fig. 2).

5) Encouraged by this interesting find, I undertook another, more careful search of Fabaceae observations from the Kobuk River Valley. This unearthed another observation by @kgofrdgmailcom (https://www.inaturalist.org/observations/301667982, see Fig. 4), which shows a plant with both flowers and pods, and an observation by @kilasiak (https://www.inaturalist.org/observations/29122961, see Fig. 1), which provides a nice lateral view of the flowers.

6) These five observations taken together provide a wealth of information, and the search for the correct species name began. My sense was that this was something new because it does not fit with any other Alaskan taxon, despite interesting similarities to certain species. Jason Grant (@jasonrgrant) joined the conversation and started checking herbarium specimens from the University of Alaska on Arctos, and kindly shared images of them with Mihail and myself. I also looked up herbarium specimens from the area through SEINet: https://swbiodiversity.org/seinet/collections/map/index.php.


Fig. 3: Astragalus sp. from Kobuk Valley National Park, observed by @popojo (see https://www.inaturalist.org/observations/304616879, CC license: https://creativecommons.org/licenses/by-nc/4.0/). This is the only observation that clearly shows the stipitate condition of the legumes.

Four different hypotheses emerged, which are discussed below:

  • Astragalus australis (= aboriginorum) [in Astragalus section Hemiphragmium]
  • Astragalus eucosmus [in Astragalus section Oroboidei]
  • Astragalus robbinsii [in Astragalus section Oroboidei]
  • Astragalus alpinus or a related taxon [in Astragalus section Astragalus]
Astragalus australis

This was my initial tentative ID three years ago (based on a vegetative plant), and it was also suggested by Jason after discovering multiple herbarium specimens from the Kobuk Dunes in the University of Alaska Herbarium database (e.g., https://swbiodiversity.org/seinet/collections/individual/index.php?occid=10041561). The similarity primarily rests on the conspicuously pubescent herbage, but is contradicted by multiple other diagnostic characters that bear more weight, i.e.:

  • the wing petals are not notched
  • the stipes of the pods is much shorter
  • the pods are densely whitish pubescent (should be glabrous or at most strigulose in australis, but the only variety that is recorded from Alaska, var. lepagei has glabrous pods according to FNA).

Furthermore, the leaflets of A. australis are also narrower than in the unidentified species.

Astragalus eucosmus

I noted resemblance of the pods with this species based on the first observation with pods (Fig. 2), where the pods appeared sessile. However, the other observation (Fig. 3) showed the pods to be stipitate and 3-sided, which clearly rules out this species.

Astragalus robbinsii

The resemblance with this species is based mainly on corolla morphology, esp. the relatively short keel and the weakly three-sided pods (the latter is much more pronounced in alpinus). Most varieties of this species have glabrous, glabrate or strigulose leaves, which are very much unlike this strongly pubescent dune plant. However, one of the three Alaska varieties recognized in FNA, var. harringtonii, has "abaxially densely gray or white villous-pilosulous" leaves (see FNA, vol. 11.2, p. 639). This is clearly visible on some of the iNaturalist observations from Alaska, e.g., https://www.inaturalist.org/observations/123756515 and https://www.inaturalist.org/observations/3519774. But the pubescence is far less developed than in the Kobuk Dunes plants, especially on the upper leaf surface, which appears to be nearly glabrous. Furthermore, var. harringtonii occurs in very different habitat along the Alaska Coast, far from the Kobuk Valley. Additional differences (i.e., calyx morphology) are mentioned below, under Astragalus alpinus.


Fig. 4. Astragalus sp. from Kobuk Valley National Park, observed by @kgofrdgmailcom (see https://www.inaturalist.org/observations/301667982, CC license https://creativecommons.org/licenses/by-nc/4.0/)

Astragalus alpinus or a closely related species

Superficially, Astragalus alpinus seems like an unlikely candidate because the widespread typical forms of this species have vibrant green leaves and usually grow in small mats in moist or rocky habitats. Despite its huge range, which spans across North America and Eurasia including Greenland the species shows surprisingly little variation. This is reflected by the fact that both POWO and FNA only recognize two varieties, the widespread var. alpinus and var. brunetianus which is restricted to Quebec, New Brunswick, Newfoundland and adjacent New England states. The latter still looks very similar to the typical variety and is mainly separated by the more appressed pubescence of the pods. However, Barneby (1964) points out that he had seen plants that differ in various aspects from typical alpinus, esp. with regard to corolla colour, length of the keel and pubescence. In fact, one of the plants that Barneby identified as A. alpinus (collected at the Kobuk Dunes in 1974, ten years after his monograph was published) obviously represents the same species that is shown in the iNaturalist observations: https://swbiodiversity.org/seinet/collections/individual/index.php?occid=6520532 (at New York Botanical Garden Steere Herbarium, NY). He probably noted the unusual morphology of the plant, and added a comment on the herbarium sheet stating: 'the "arcticus" type, but an ecotype of that'. In view of the new data gathered, I am strongly inclined to consider this population as something new (at least a new variety of A. alpinus, if not a new species altogether). My reasoning is based on the following diagnostic characters:

  • the greatly shortened keel of the corolla, which is unlike any other alpinus form seen in North America (the keel should be subequal in length to the wing petals, typically slightly longer or as long as the latter, rarely slightly shorter)
  • the elongated, ascending stems and non-mat forming growth type, which are an obvious adaptation to the dune environment with its ever shifting sand
  • the dense, silvery pubescence
  • the long stipes of at least some pods. This requires further examination of herbarium specimens since the pods of some of the mentioned iNat observations appear sessile or subsessile
  • possibly the white pubescence of the pods (usually black in mature pods of alpinus). This is hard to assess on the pictures available and needs to be further studied on appropriate herbarium material.

One possible hypothesis is that this is merely an ecomorph of A. alpinus induced by the unusual ecological conditions of the dune habitat. In fact, most of the distinctive morphology can be interpreted as an adaptation to the habitat. However, the strikingly shortened keel of the corolla cannot be interpreted that way. It is perhaps the strongest indicator for a separate taxonomic entity. It is furthermore noteworthy that typical A. alpinus also occurs in the Kobuk Dunes area, but in different microhabitats (e.g., "among hummocks of willow-grass": https://swbiodiversity.org/seinet/collections/individual/index.php?occid=10075643). If both taxa occur in close proximity without interbreeding or intergrading, it would lend further support to the idea that they are in fact distinct species. DNA sequencing of both forms should conclusively answer this question.

The close relationship with A. alpinus is supported by the three-sided pods and the configuration of the calyx teeth, which differs from the similar A. robbinsii: This character has apparently not been mentioned in the literature but has been proven constant through the examination of hundreds of observations on iNaturalist. In robbinsii, the upper calyx teeth are displaced laterally and ventrally, i.e. they are broadly separated from each other but are very close to the lateral teeth. In both alpinus and the Kobuk Dunes plants, the calyx teeth are in a more dorsal position and closer to each other (more broadly separated from the lateral teeth than in robbinsii). This is well illustrated in the line drawings of both species on p. 632 of FNA Vol. 11.2, as well as in numerous iNaturalist observations, e.g.:

An online search uncovered additional material of the Kobuk Dunes Astragalus (identified as A. alpinus) in the University of Alaska Herbarium (ALA), e.g.:

Interestingly, the herbarium specimen that was identified by Barneby (https://swbiodiversity.org/seinet/collections/individual/index.php?occid=6520532) shows a diagram of the calyx, probably drawn by Barneby himself. Unfortunately, we don't know his thoughts about what he observed.

Hopefully, this journal post will stimulate further discussion and a more thorough investigation of this intriguing Astragalus population.

Posted on October 3, 2025 06:06 AM by matthias22 | 6 comments | Leave a comment

February 21, 2025

Updates to the Checklist of Apoid Wasps of Canada, Alaska and Greenland


Image: Sphex ichneumoneus from Bow Island, Alberta (see https://www.inaturalist.org/observations/239328539)

The published Checklist can be downloaded here: https://doi.org/10.3897/jhr.98.143759
A journal post that summarizes the findings, including acknowledgements of the contributions of the iNaturalist community here: https://www.inaturalist.org/journal/matthias22/104693-checklist-of-apoid-wasps-of-canada-alaska-and-greenland-now-in-press.
If you become aware of any potential new records please let me know, and I will verify them and add them here.

New records that came to light after the publication of the Checklist on Feb 13, 2025

Alaska

Crabro nigriceps: https://www.inaturalist.org/observations/371040421 by @awenninger (12 Jun 2026)
Crossocerus elongatulus: https://www.inaturalist.org/observations/393032712 by @awenninger (21 Aug 2026)
Crossocerus minimus: https://www.inaturalist.org/observations/389155856 by @awenninger (2 Sep 2026)
Ectemnius atriceps: ♂, https://www.inaturalist.org/observations/372679003 and ♀, https://www.inaturalist.org/observations/372679005 by @awenninger (17 Jun 2026)

Yukon

Solierella nigrans: 1 ♀, Hwy 4, 16 km N Jct. Hwy 1, 9 Jul 1987, B.F. & J.L. Carr (G. Hilchie private coll.) (12 May 2025)

British Columbia

Tachytes fulviventris: https://www.inaturalist.org/observations/320208608 by @shawnb2 (26 Mar 2026). Specimen collected and deposited at the Royal Alberta Museum.
Oxybelus robertsonii: https://www.inaturalist.org/observations/294703748 by @shawnb2 (13 Apr 2026). Specimen collected and deposited at the Royal Alberta Museum.

Alberta

Hoplisoides hamatus: 1 ♀, Pakowki Sandhills, 24 Jun 2026, M. Buck (Royal Alberta Museum) (21 Aug 2026)
Steniolia elegans (New to Canada): 1 ♂, Milk River Natural Area, 5-7 Aug 2025, pitfall traps, G. Hilchie (GJHC00003654; to be deposited at the Royal Alberta Museum). Identified by M. Buck (21 Aug 2026)
Crossocerus decorus (New to Canada): 1 ♀, South Saskatchewan River at Range Road 23, 1 Jul 2026, M. Buck (Royal Alberta Museum) (21 Aug 2026)
Rhopalum pedicellatum: https://www.inaturalist.org/observations/163896884 by @pbulman (20 Feb 2025)
Tachysphex clarconis: 2 ♂, Pakowki Sandhills, 9 Jun 2025, M. Buck (PMAE.IZ00181004, PMAE.IZ00181006; Royal Alberta Museum). Other specimens from the same locality. (21 Aug 2026)
Oxybelus cressonii: https://www.inaturalist.org/observations/314862282 by @matthias22 (18 Sep 2025). Specimens deposited at the Royal Alberta Museum.
Pemphredon rileyi: 1 ♀, Waterton Lakes National Park, Red Rock Canyon Road, 49.114°N 113.9922°W, 8 Jul-16 Aug 2010, David Langor (Northern Forestry Centre, Edmonton). (7 Apr 2025)
Cerceris vicina (New to Canada): 1 ♀, Kennedy Coulee Ecological Reserve, 7 Aug 2025, G. Hilchie (GJHC00003732; to be deposited at the Royal Alberta Museum). Identified by M. Buck (21 Aug 2026)

Saskatchewan

Pisonopsis clypeata: https://www.inaturalist.org/observations/168472447 by @sarasims (18 Feb 2025)

Manitoba

Passaloecus lineatus: 1 ♂, Winnipeg, Little Mountain Park, 2 Jul 2022, A. van Dyk (WRME_AVD1153, J.B. Wallis / R.E. Roughley Museum of Entomology, University of Manitoba). Identified by Jason Gibbs, confirmed by M. Buck (23 Sep 2025).
Pemphredon baltica: 1 ♀, Lac du Bonnet, 25 Jul 1948, G.L. Warren (J.B. Wallis / R.E. Roughley Museum of Entomology, University of Manitoba). This record should have been included in the paper but was overlooked. (4 Apr 2025)
Podalonia clypeata: 1 ♀, Birds Hill Provincial Park, 22 Jul 1978, T.D. Galloway (JBWM0289870, J.B. Wallis / R.E. Roughley Museum of Entomology, University of Manitoba). Identified by Jason Gibbs, confirmed by M. Buck (14 May 2025).

Ontario

Rhopalum gracile: https://www.inaturalist.org/observations/222721951 by @rileywalsh (20 Feb 2025)

New Brunswick

Ectemnius stirpicola: https://www.inaturalist.org/observations/388149264 by @nbdragonflyguy (20 Aug 2026)
Plenoculus davisi: https://www.inaturalist.org/observations/380479086 by @jdee (4 Aug 2026)
Oxybelus sericeus: https://www.inaturalist.org/observations/10601929 by @stubirdnb (20 Feb 2025)

Nova Scotia

Clitemnestra bipunctata: https://www.inaturalist.org/observations/303549737 by @infinitemra (5 Jun 2026)
Oxybelus sericeus: https://www.inaturalist.org/observations/172080325 by @kathleenfspicer (20 Feb 2025)
Ammophila fernaldi: https://www.inaturalist.org/observations/227233434 by @spenner (5 Mar 2025)

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Reinstated literature records

Alberta

Crabro largior: 1 ♀, Kootenay Plains Ecological Reserve, 6 Jul 2025, M. Buck (PMAE.IZ00180497, Royal Alberta Museum). Bohart (1976) recorded this species from Banff, Alberta. The record was deemed doubtful and excluded from the checklist because no voucher specimens could be located, and because females of this species are frequently confused with other species of Crabro (21 Aug 2026)

============================

Validated literature records

Alaska

Crossocerus leucostoma: Mentioned by Krombein (1979). https://www.inaturalist.org/observations/389153549 by @awenninger (29 Aug 2026)

Alberta

Crabro pleuralis: Mentioned by Krombein (1951). 1 ♀, Waterton Natl. Pk. (Northern Forestry Centre, Edmonton, Alberta) (17 Mar 2025)

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Occurrence status updates

Ontario

Eucerceris zonata: https://www.inaturalist.org/observations/127938687 by @abieticola. Occurrence status was given as "unclear, possibly extirpated" in the Checklist. This is the first record of this species from Ontario since 1955, see discussion in Leclerc et al. (2025): https://doi.org/10.22543/0090-0222.2489.

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Corrigenda

Genus Lyroda

A reference to the most recent key to Nearctic species was omitted by accident:
Khvir VI, Pulawski WJ (2020): A revision of the New World Lyroda Say, 1837 (Hymenoptera: Crabronidae). Proceedings of the California Academy of Sciences (Series 4), 66: 315–330. https://researcharchive.calacademy.org/research/entomology/entomology_resources/hymenoptera/sphecidae/copies/Khvir_Pulawski_2020.pdf (8 Apr 2025)

Posted on February 21, 2025 05:58 AM by matthias22 | 0 comments | Leave a comment

January 12, 2025

Checklist of Apoid Wasps of Canada, Alaska and Greenland now in press


Image: Ammophila ferruginosa from the Milk River Natural Area in Alberta (see https://www.inaturalist.org/observations/249443286)

Update 13 Feb 2025: the Checklist has been published. Open access here: https://doi.org/10.3897/jhr.98.143759

I am pleased to announce (with my co-author Andy Bennett at the Canadian National Collection of Insects in Ottawa) that the apoid wasp chapter of the Checklist of Hymenoptera of Canada, Alaska and Greenland is now in press with the Journal of Hymenoptera Research, and will be published soon. Once it is published, the paper can be downloaded for free from the journal's website: https://jhr.pensoft.net/. The apoid wasp checklist is the fourth instalment of a collaborative series of checklists, which will ultimately cover the entire order Hymenoptera. For an introduction to the series see Bennett (2021): https://doi.org/10.3897/jhr.82.60054. Apoid wasps is the group of wasps that is currently classified as Sphecidae, Ampulicidae and Crabronidae on iNaturalist (for North America). Based on new developments in phylogenetic systematics, the Crabronidae is now divided into eight families (Crabronidae s.s., Mellinidae, Astatidae, Bembicidae, Psenidae, Philanthidae, Pemphredonidae and Ammoplanidae). I am announcing the new Checklist here on iNaturalist because the study is in part based on data from this website, which is gratefully acknowledged.

The goal of the Checklist was to document the apoid wasp fauna of Canada by province and territory in addition to Alaska and Greenland (no species are recorded from the latter). This has never been done before as the previous Catalog of Hymenoptera in America North of Mexico (published in 1979: https://www.biodiversitylibrary.org/page/4575614) often only provided summary range descriptions without detailing exactly in which province or territory each species occurred.

Some content highlights in brief:

  • Canada has 531 described species and 86 genera of apoid wasps (plus at least 20 undescribed species)
  • this is a 124% increase for species and 42% for genera compared to the Catalog of Hymenoptera in America North of Mexico published in 1979
  • Alaska has 63 species (including 31 new records) and 24 genera (8 new records), all of which are also known from Canada
  • overall, the Checklist provides 2,109 provincial, territorial and Alaskan records, one third of which are new
  • 11 species are newly recorded from North America and the New World, 8 of which are accidental introductions
  • 70 species are newly recorded for Canada (13% of the total fauna)
  • one species (Crabro dietrichi) is newly recognized as the only apoid wasp species endemic to Canada (only known from Prince Edward Island)
  • 23 introduced species are recorded from Canada (only one of them occurs in Alaska as well), an increase of 53 %
  • the vast majority of records in this Checklist is based on verified museum specimens, verified image-based observations (iNaturalist, Bugguide) or verified sequenced specimens (https://portal.boldsystems.org), only 1.6% are based on unverified (but credible) literature data
  • 147 previously published erroneous records were corrected or excluded as unlikely: 33 Canadian records, 112 provincial/territorial records and 2 Alaskan records
  • a critical taxonomic review of the fauna resulted in 6 species reinstated from synonymy and 14 new or revised synonymies at the species level
  • type specimens or images of type specimens of 57 nominal species were examined in order to clarify the taxonomy of problematic species
  • the following topics are also discussed: the biogeography of Canadian and Alaskan species, including Holarctic species and species shared with other biogeographic regions, distribution patterns within the Nearctic region, remarkable new records, geographic prevalence of nesting habits, distribution patterns and introduction timelines of introduced species, faunal change

The contribution of iNaturalist and Bugguide

iNaturalist and Bugguide.net contributed in significant ways to this project:

  • four new Canadian records were first observed on iNaturalist and Bugguide (5.8% of new Canadian records)
  • 69 new provincial/territorial/Alaskan records were first observed on iNaturalist and Bugguide (9.8% of all new regional records)
  • 2 new introductions to North America were first observed on Bugguide (25% of new introductions)
  • 100 observations (85 on iNaturalist, 15 on Bugguide) are cited individually in the paper
  • significant range expansions of ten species of Sphecidae and Crabronidae in southern Ontario and Quebec are documented by iNaturalist data and are suspected to be caused by a warming climate
  • 48 images of live wasps (56% of all genera) in the image gallery were kindly contributed through observers on iNaturalist and Bugguide (tagged below - not including two of my own which are also on iNaturalist :-)

The significance of citizen science data, esp. those on iNaturalist is discussed in this paper. The iNaturalist dataset for Canadian/Alaskan apoid wasps (Sphecidae, Ampulicidae and Crabronidae) is extensive and characterized as follows:

  • over 36,800 observations until the end of 2024, with >25,100 identified to species, 18,600 of which are Research Grade
  • on average roughly 6,900 observations submitted per year between 2021 and 2024
  • 229 species are documented from Canada and Alaska, a surprising 43% of all the species known from the area
  • between 2019 and 2024, an average of 23 species were newly added each year for Canada and Alaska
  • the dataset shows a strong geographic bias with 62% of all observations made in Ontario (which only has one third of the population of Canada and Alaska combined)
  • iNaturalist data revealed an unexpected diversity of apoid wasps in one densely populated urban centre (93 documented species in the City of Toronto, including two new Canadian records and several rare species)
  • one critically endangered species had not been collected in Toronto since 1918 and was currently only known from one other extant locality in Ontario
  • the 8 top identifiers of this dataset each identified over 1,000 observations (maximum over 6,000), tagged below

Acknowledgements

Observations by the following iNaturalist contributors are cited in this publication or their images reproduced with permission (ordered alphabetically by username): @alainhogue, @alice_abela, @ama75, @apples58, @awenninger, @bob15noble, @bobharding, @bug_eric, @c704938, @carrollperkins, @cholmesphoto, @cibrink, @david_turgeon, @dbeadle, @dbmcc09, @deannadodgson, @dominik_ramik, @donnalucas, @dracoabe, @elepaio, @ellyne, @etienne111, @ewren, @freduchini, @gabohq, @gbudyk, @gordhutchings, @grivesolitaire, @hailauren, @hcray, @heatherholm, @ipat, @jacoboffairmont, @jaegerpilot, @jasonheadley, @jcowles, @jdee, @jenstr, @jfmantis, @johanna_s, @juju98, @k087, @kathleenfspicer, @krisskinou, @kyukich, @lenachiasson, @louiseinva, @ludoleclerc, @lukef2006, @mathisb21, @mhking, @moragschonken, @mowgly1, @muir, @naturecitizen, @naturefiend, @nbdragonflyguy, @nickbedard, @nickbelliveau, @nonomay, @nubiti, @owenstrickland, @paulschrijvershof, @pei-ott, @phil_crimson, @piskomantis, @randylauff, @rileywalsh, @samree, @spavery [now @averywells], @steve_kerr, @stevemirick, @suelabbe, @suvijohn, @sydcannings, @thejasperpatch, @tmurray74, @u_phantasticus, @watercolorist, @whaichi, @willkuhn, @y-zhou.

Observations by the following Bugguide contributors are cited in this publication or their images reproduced with permission (ordered alphabetically, cited by their iNaturalist username if applicable): Angus MacLean, Arthur Scott Macmillan, Christopher Adam, Daniel Horner, Jean Brodeur, Latour, @leoguy, @richardmig, @stubirdnb.

The work of 1,495 identifiers (as of January 2025) of Canadian/Alaskan apoid wasps on iNaturalist is gratefully acknowledged (see https://www.inaturalist.org/observations?hrank=family&place_id=6712,6&taxon_id=47222&view=identifiers&without_taxon_id=630955). The top identifiers with >1,000 identifications include (ordered by decreasing number of identifications): @johnascher, @susanna_h, @matthias22, @bdagley, @rileywalsh, @juan_sphex, @bullema, @jfmantis. Thank you everyone!

Posted on January 12, 2025 02:39 AM by matthias22 | 33 comments | Leave a comment

January 3, 2025

Fabaceae flower bud galls


Image: Flower bud galls on Hedysarum alpinum from the Kootenay Plains Ecological Reserve in Alberta: https://www.inaturalist.org/observations/256730340

Note: this is a living document. I first published this post in January 2025, but I am keeping it up to date with any new information that comes to my attention (last update: 22 April 2026).

This post is about flower bud galls in several genera of Fabaceae that appear to be poorly documented or even new to science. I first came across these galls during my field work in Alberta, Canada, in the summer of 2024. Subsequently I discovered more examples of them from all western Canadian provinces here on iNaturalist. Since then, the list of observations and the number of host species has steadily grown (see below). My primary go-to resource for galls is Gallformers.org (https://www.gallformers.org), a formidable website for North American galls developed by Adam Kranz, Jeff Clark, Timothy Frey and their team (see iNat blog post: https://www.inaturalist.org/posts/83909-identifier-profile-gallformers). When I first searched on gallformers.org, I could not find any kind of flower galls for the genera I found them on (Astragalus, Lathyrus, Vicia, later also Hedysarum - they have been added since). Furthermore, the galls were unknown to Adam and Timothy who I consulted.

Description of galls

The galls in question are integral flower bud galls that cause a variable amount of swelling of the bud, particularly in the calyx region. The swelling ranges from slight to severe, sometimes rupturing the calyx. In addition, the buds are usually slightly stunted (shorter than normal flower buds), and they do not open, except often in Lathyrus cochroleucus, but then the petals are malformed and wither with delay. In some species, the greatly enlarged, galled buds stand out immediately from normal buds, in others the difference is more subtle and can be easy to overlook. In most cases, however, they are easily recognized. Similar galls have apparently not been recorded before from North America but are known to occur in Europe and Japan, for example in Lotus corniculatus (caused by Contarinia loti: https://bladmineerders.nl/parasites/animalia/arthropoda/insecta/diptera/nematocera/cecidomyiidae/cecidomyiinae/cecidomyiidi/cecidomyiini/contarinia/contarinia-loti/) and in Pongamia pinnata (caused by Ishigakidiplosis karamae: https://doi.org/10.1093/zoolinnean/zlad152).


Image: Flower bud gall on Astragalus drummondii from Willow Creek Coulee near Drumheller, Alberta: https://www.inaturalist.org/observations/251264402

Gallformer species

At present, all we know is that these galls are caused by gall midges (family Cecidomyiidae), but both genus and species are unknown. I suspect that they are all caused by species in a single genus, but we don't know how many species are involved. The considerable host range (see below) and ecological breadth (habitat, elevation) suggests that several species are involved. The fact that these galls are caused by gall midges was first discovered on Astragalus drummondii galls (see previous image and link). I harvested a couple of the galled inflorescences and put them in a vial to dissect them later. I frogot to do so, but a couple of days later the vial crawled with tiny gall midge larvae. Unfortunately, I forgot to take a picture of them, but I am certain they were cecidomyiids. Later I also dissected galls on Hedysarum sulphurescens and was able to document them photographically (see following image).


Image: Gall midge larva from flower bud gall of Hedysarum sulphurescens, exposed by opening the gall. Found at Kootenay Plains ER, Kinglet Lake Trail, Alberta: https://www.inaturalist.org/observations/327206252

Context: Cecidomyiidae galls on Fabaceae in Alberta

Currently, the Vascular Flora of Alberta (5th printing, 2022) recognizes 23 native and introduced genera of Fabaceae in Alberta. A quick search (back in 2024) for galls on gallformer.org for these genera yields very few known Cecidomyiidae galls. The only flower galls occur on introduced clovers (Trifolium hybridum, pratense, repens) and are caused by two species of Dasineura (e.g., https://www.gallformers.org/gall/5159). Apparently, the galled flowers undergo little morphological modification and are not easily detected. However, Fabaceae galls that are similar to the ones described here are known to occur in Europe, for example in Lotus corniculatus (caused by Contarinia loti): https://bladmineerders.nl/parasites/animalia/arthropoda/insecta/diptera/nematocera/cecidomyiidae/cecidomyiinae/cecidomyiidi/cecidomyiini/contarinia/contarinia-loti/

Otherwise, only five other genera of Fabaceae that occur in Alberta are recorded to have galls: Astragalus, Dalea, Lupinus, Lathyrus, and Thermopsis. They include leaf and stem galls. The only cecidomyiid genera recorded are Dasineura (on Dalea, Lupinus, Trifolium) and Neolasioptera (on Lupinus).


Image: Flower bud galls on Astragalus bisulcatus from Willow Creek Coulee near Drumheller, Alberta: https://www.inaturalist.org/observations/251279647

Host spectrum

So far, I found galls on three tribes and four genera of non-woody Fabaceae, all of which appear to be unrecorded in the literature:

  • Fabeae: Lathyrus, Vicia
  • Galegeae: Astragalus
  • Hedysareae: Hedysarum The known Astragalus hosts are members of 17 different sections (including species from the U.S.): Argophylli, Bisulcati, Scaposi, Cusickiani, Lonchocarpi, Ervoidei, Drummondiani, Ocreati, Scytocarpi, Onobrychoidei, Diphysi, Genistoidei, Leptocarpi, Pectinati, Preussiani, Oroboidei and Drabellae.

These are probably the only Fabaceae genera affected in Alberta. The largest number of host species has been found in Astragalus (23 spp., including 11 spp. that have only been observed in the U.S.), followed by Hedysarum (3 spp., including one only from the U.S.). Here are all gall observations listed by host (province or state in parentheses):

[NB: all observations, except for some of my own, were originally incidental, i.e. submitted as plant observations without acknowledging the presence of galls]

Classification

On gallformers.org, the galls are currently classified into five groups, two for Astragalus and one each for the other genera. These are mere groups of convenience and do not reflect species since the taxonomy of the gallformers is still completely unknown. Below are the groups and their gallfomer codes:


Image: Flower bud galls on Astragalus pectinatus from Lethbridge, Alberta, observed by Taija Cahoon (@taijavu): https://www.inaturalist.org/observations/251470208 (© Taija Cahoon, used with permission)

Biogeography

Widespread in Canada from British Columbia to western Ontario. Currently, the northernmost observation is from Sikanni Chief Falls in the Peace River Region of British Columbia (57.2587°N, Lathyrus ochroleucus, see https://www.inaturalist.org/observations/300000976) and the easternmost from Goetzville, Michigan (84.2392°W, Lathyrus ochroleucus, see https://www.inaturalist.org/observations/13554422). I have not searched enough for these galls in the United States to provide a meaningful range description. Currently, U.S. records include the following states: Montana, North, Dakota, South Dakota, Colorado and New Mexico. These are also the states where I have identified the most host plants. I anticipate that these galls also occur in other states west of the Rocky Mountains, but I have not searched for them there. The southernmost observation is currently from New Mexico (35.1259°N, Astragalus praelongus, see https://www.inaturalist.org/observations/351537859).


Image: Flower bud gall on Hedysarum sulphurescens from Bluerock Wildland Prov. Pk. in Kananaskis country, Alberta: https://www.inaturalist.org/observations/257071006

Habitat

The host plant spectrum does not only represent a significant taxonomic diversity, it also includes species from different types of habitats and ecozones. The Astragalus hosts include mostly prairie species (A. bisulcatus, A. drummondii, A. pectinatus) but other host species are typical of wooded areas, both in parkland and in the montane zone of the mountains, some even reaching the lower alpine zone. More recent findings are from semi-arid (high desert) areas of New Mexico. The highest elevation is currently represented by a gall on Hedysarum sulphurescens from Rover Peak in the East Kootenays of British Columbia (2,290 m a.s.l., https://www.inaturalist.org/observations/32199371). The majority of mountain observations is from the montane zone, but at least two others are also from the subalpine or lower alpine zone (Hedysarum alpinum, 2,040 m, https://www.inaturalist.org/observations/178486497; Astragalus vexilliflexus, 1,960 m, https://www.inaturalist.org/observations/257181429).

Outlook

Much still needs to be learned about these galls, especially which species cause them. If you find any flower bud galls please let me know so they can be added to the list above.


Image: Flower bud gall on Astragalus multiflorus from the Red Deer River Valley 2.5 km east of Western Monarch, Alberta: https://www.inaturalist.org/observations/257071006

Acknowledgements

Many thanks to Adam Kranz and Timothy Frey for their kind help with galls, and for adding these galls as unknowns to gallformers. org. A special thank you to @andershastings who alerted me to several interesting gall observations from Colorado, including five new host records (Astragalus anisus, A. convallarius, A. hallii, A. nuttallianus and A. schmolliae)!

Posted on January 3, 2025 12:45 AM by matthias22 | 8 comments | Leave a comment

February 3, 2024

Finding Oxytropis nana


Image: Putative Oxytropis nana from Natrona Co., WY, observed by FrontRangeWildflowers: https://www.inaturalist.org/observations/151764972 (© CC-BY-NC)

The Wyoming Locoweed (Oxytropis nana) is a rare species whose entire documented range is within the borders of Wyoming: https://bonap.net/MapGallery/County/Oxytropis%20nana.png (see also the 2023 Fabaceae Volume of Flora of North America).

Welsh (in FNA, 2023) describes the species as intermediate between Oxytropis sericea and O. multiceps. It also closely resembles O. lagopus. In both species (except var. conjugans of lagopus, which does not occur in Wyoming) the pods remain fully enclosed in the accrescent calyx. Welsh (2023) does not provide any diagnostic features for flowering plants which makes it very difficult to ID observations here on iNaturalist (most of which are made in the flowering stage).

Oxytropis nana herbarium specimens on SEINet: https://www.swbiodiversity.org/seinet/taxa/index.php?tid=93440&taxauthid=1&clid=0

Welsh's (2023) description: [to be added]

I have done my fair share of Oxytropis identifications on iNaturalist and have become familiar with a few species, but I am not an expert by any stretch. Oxytropis nana is completely unfamiliar to me but my hope is that the community might figure out a way to characterize this species based on photographs. I am therefore inviting everybody who is interested in Oxytropis to participate and share their insights.

As a first step I have assembled all observations that have at least one active O. nana ID. Many are sitting at genus or tribe level because they have other, conflicting IDs. I also added a couple of observations that have no nana ID but might be relevant. Some are from outside Wyoming and therefore likely misidentified, but I have included them here to give them fair consideration. When I assembled this list, I noticed that the IDs are very heterogenus (not surprising for a poorly known species). I therefore sorted them into morphological groups. The characters used for that are mentioned in my previous blog post on Oxytropis besseyi and related species: https://www.inaturalist.org/journal/matthias22/89224-identification-of-oxytropis-besseyi-lagopus-and-similar-species

Based on this, I was able to categorize observations with Oxytropis nana IDs into roughly five groups. My impression is that probably less than a handful are true nana, all the others resemble other species and are likely misdentified. However, it is also possible that O. nana simply can't be distinguished from other species except by fruit. In this case, I would expect that true nana are most likely found within Group I (lagopus lookalikes) and perhaps Group IV (oddball sericea-like plants with villous calyces).

Below are my groups. If you would like to participate in this review let me know what species each group represents, and let me know if I misplaced any observations. Also let me know about any observations I might have missed. Thanks in advance for your help!

True nana?

Group I (similar to lagopus):

[Note: BONAP does not mention O. nana from Teton Co.: https://bonap.net/MapGallery/County/Oxytropis%20nana.png]

Group Ib (pods only, calyx inflated, fully enclosing pod):

[Note: this should be var. lagopus]

Group Ic (pods emergent from calyx):

[Note: this should be var. atropurpurea but not clear how to distinguish them from besseyi without flowers.]

Group II (similar to besseyi):

Group IIb (pods only):

[Compare also to Group Ic (see note there). Note: BONAP does not mention besseyi from Sublette Co.: https://bonap.net/MapGallery/County/Oxytropis%20besseyi.png]

Group III (similar to lambertii):

Group IV (similar to sericea):

Group IVb (sericea? high elevation plants of compact growth habit, with white or yellow flowers):

Posted on February 3, 2024 11:41 PM by matthias22 | 12 comments | Leave a comment

January 31, 2024

Identification of Oxytropis besseyi, lagopus and similar species


Image: Oxytropis besseyi from Bozeman, MT, observed by Matt Lavin: https://www.inaturalist.org/observations/106024442 (© CC-BY-SA)

Identifying Oxytropis (locoweeds) can be a bit of a challenge. As with many plants, published keys often use characters that are hard to see on pictures, or they require fruit when there are only flowers, etc.

Oxytropis is one of the genera I regularly identify, and I am going to share here what I learned while going through Oxytropis observations from Montana. Oxytropis besseyi and lagopus were new species to me because I live in Canada where both species have very small and localized ranges.

Literature used: Flora of North America Vol. 11, Fabaceae (2023); Manual of Montana Vascular Plants (2012). Some of the characters presented here are not mentioned in the literature, specifically the shape of the wing petals. Most taxonomic work is done on pressed herbarium specimen where some of the three-dimensional characteristics of the flowers are no longer observable. Therefore, characters like these are easily missed, and they wouldn't be very useful identifying herbarium specimens. What I am putting forward here are hypotheses, and in science every hypothesis needs to be tested. Therefore, please let me know if you find a mistake or see something that can be improved. But now to the meat:

Introductory note: Oxytropis flowers are variable in shape and colour. It is very common to find misshapen or atypical flowers where petals are bent in ways that are not normal. Please take that into consideration when using the diagnostic characters below. Try to assess a number of flowers, if possible, and disregard the ones that fall out of line. It is also important to consider the stage of the flower. Flowers that are in the process of unfolding have the wing petals closer together than mature flowers. Withering flowers are often bent out of shape. The descriptions below apply to mature flowers. The literature uses the presence vs. absence of black hairs on the calyx to distinguish lagopus from besseyi. I have not been able to see black hairs on any of the images here on iNaturalist. This character probably requires higher magnification.

Oxytropis besseyi

  • wing petals spreading widely (usually at least 90°), openly exposing keel
  • upper margins of wing petals approximately as far apart as lower margins (petals not tilted)
  • calyx villous, predominantly with spreading hairs
  • only basal part of mature pod sheathed by calyx (which is at most slightly inflated in fruit)
  • racemes 3-22-flowered, subcapitate to slightly elongate (esp. in fruit)
  • most common in mountainous areas (valleys to subalpine), marginal in prairie zone, but reaches southern Saskatchewan
  • blooming later than lagopus at the same elevation (June 5 to Aug 10 in Montana based on iNat observations, n=69)

Examples:

Oxytropis lagopus

  • wing petals either not spreading widely (< 90°) or else petals tilted inwards dorsally
    • upper margins of wing petals usually closer together than lower margins or else wing petals not wide spreading
    • calyx villous, predominantly with spreading hairs
    • mature pod usually fully enclosed by inflated, persistent calyx (var. lagopus), or rupturing slightly inflated calyx in var. conjugans and atropurpurea)
    • racemes 5-18-flowered, subcapitate to slightly elongate
    • most common in mountainous areas (valleys to subalpine), marginal in prairie zone, but reaches Milk River Ridge in southern Alberta
    • blooming earlier than besseyi at the same elevation (April 27 to Jun 29 [one outlier: Jul 23] in Montana based on iNat observations, n=70)

Examples:

Oxytropis lambertii

  • wing petals convergent above (often more or less touching), ± concealing keel
  • lower half of wing petals more or less parallel to each other or tilted outward
  • calyx predominantly with decumbent hair (few spreading hairs) [unlike lagopus, lambertii]
  • only basal part of mature pod sheathed by calyx (which is not inflated in fruit)
  • racemes 8-45-flowered, more elongate than in the other species (esp. in fruit), flowers well spaced
  • leaflets often very narrow
  • occurs mostly in prairie zone in north-central U.S. but reaches foothills, extends east to Manitoba, MN and IA
  • blooming May 7 to Jul 8 in MT and SD based on iNat observations (n=217)

Examples:

Posted on January 31, 2024 05:41 AM by matthias22 | 5 comments | Leave a comment

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