Journal Post Photos Fixed (Mostly)

For those who weren't aware, iNaturalist changed the URLs of many of the photos (more info here, here, and here). This broke the vast majority of my photo identification resources. I think I've finally gotten them all fixed now (well, all the important identification guides that you can link to here). Please let me know if you find any of my resources that have broken photo links.

As I have time, I'm slowly trying to figure out how to create guides moving forward as the current method is unstable (see here). I haven't decided yet. You're welcome to leave suggestions and I would especially value alternative strategies people have tried. However, I may be slow in reading and responding to them as ID guides are not my priority at the moment. Whatever method used should try to balance three features: stability, access to the iNaturalist community, and ease of construction. The journal posts balanced all categories pretty well until stability became an issue.

由使用者 nathantaylor nathantaylor2022年02月03日 01:47 所貼文 | 3 評論 | 留下評論


Euphorbia presentation at BRIT!

I thought I should let you all know that I'm presenting on Euphorbia sect. Anisophyllum next week. It will be held on Tuesday (Feb 1st) from 12:00-1:00. I'll talk about my Master's research and my experience integrating iNaturalist into sandmat taxonomy. If that sounds interesting, feel free to join!

Here's a link to the page: https://brit.org/events/euphorbia/

由使用者 nathantaylor nathantaylor2022年01月27日 04:48 所貼文 | 5 評論 | 留下評論


Test journal post

BONAP map:

Photo from iNaturalist:

由使用者 nathantaylor nathantaylor2020年12月01日 21:00 所貼文 | 2 評論 | 留下評論


Change is a good thing

So, I think it's time I talk about how I've had to and will continue to cut back on my identifications. To skip to the point for those not interested in the long story, I have and will continue to cut back severally on the number of identifications I provide on iNaturalist and focus only on the most important ones to me (more details about what "most important" means in bold below).

This decision has been a mixture of conscious decision-making and a natural progression as my life and iNaturalist change. The natural parts have come via the record high numbers of observations continually being uploaded and my desire and need to focus on matters closer to home. The conscious decision-making has come in the form of figuring out a new balance to my life and iNaturalist so that I can stay engaged without being overwhelmed. There's no way to sugar coat it, this has been a hard year for everyone and with prospects of starting a doctoral program at Oklahoma State University has made me think about what I want out of iNatualist and my research in general.

My goal used to be to curate all the US Euphorbias, all of sect. Anisophyllum worldwide, and all the plants of the Llano Estacado and surrounding areas. I have added Texas Euphorbiaceae to that list a couple of times. Excluding Euphorbiaceae and the other random groups, I would have occasionally tried to curate, the records I have been focusing on have grown from roughly 2,623 observations per month from last year (about 31,474 for all of 2019) to nearly 3,941.5 observations per month this year (about 23,649 for these first 6 months of 2020 alone). This is a 50% increase, but the trend is upward growth, so I would not be that suprised if the overall figure ends up at a 70% increase by the end of the year (last year's growth for the US Euphorbias was 43%). I suppose it's still possible to expect a full doubling by the end of the year. The Llano Estacado observations for this year, in particular, are just 652 away from matching the 12,351 observations made last year. I am extremely proud and encouraged by this growth even if it does exceed my limitations. To put those numbers in perspective, the average for all of 2019 was about 86.2 observations/day. That average has risen to about 129.5 observations/day for 2020. Of course, these are usually clustered in the growing season. For this month (June 2020), the average has been 226 observations/day! This is what identification fatigue looks like in cold hard numbers.

With this in mind, I can't keep the same goals I have had. I have cut back severely these last couple weeks and have felt a lot better for it. I've even had some time to dabble in botanical illustration. At this point, it isn't just a question of time but also a question of rebalancing my life outside of iNaturalist. Every hour I spend on iNaturalist IDing Euphorbia maculata in cities that have a hundred others just like them is an hour I could spend writing documents that could help shape the way we all view the species and help everyone get better at identifying this and other species as a whole. When I write anything on iNaturalist, I want to focus on this meathod and not try to get keep everything tidy as I wanted to in the beginning. That's ultimately what I want and my time on iNaturalist needs to facilitate these goals and not hinder them as has been the case for many months now. I think it will be better for me, iNaturalist, and our understanding of the natural world in general. As for what my future plans are regarding iNaturalist, I will have to see how much time I have when I start my Ph.D. studies, but my hope is to focus on what follows:

Llano Estacado: Putting together genera treatments as I have been doing and only IDing the genera I'm currently working on.
US Euphorbias: Except for sect. Anisophyllum and special requests, I'm putting this group on hold. I may try to complete some of my ideas for guides in the project, but I have to cut back here.
Worldwide sect. Anisophyllum: Focus on novel observations and publishing articles that have been on the backburner for over a year. I hate to say this, but that especially means no more IDing E. maculata across most of the US except by special request.

Ultimately, I suspect I will have to cut the above down to one or maybe two once I start grad school, but those are my iNaturalist goals facilitating my broader goals of creating a flora of the Llano Estacado and monographing section Anisophyllum. Concerning special requests, I still intend to offer my expertise whenever someone asks and really hope I don't get so busy that I have to start ignoring them, but please be understanding if I do. So many aspects of my life and iNaturalist are changing and it will be hard to predict where I end up as time goes on. I hope it never comes to this, but if I have to prioritize, my first priority will always be towards those who both want to learn and are willing to help others identify. The second will be towards those who want to learn how to ID the species. And lastly are those who simply want an ID. I will also prioritize observations that I know without having to look anything up. Looking up information takes a lot of time when multiplied over many observations and I will almost certainly have to cut or severely limit these in the future.

It may not seem like it, but this is a big change for me, definitely the biggest internet usage change and probably a lot bigger than when I decided to not check Facebook every day. I have spent nearly every day (with the typical exception of Saturday) for the past few years identifying plants on iNaturalist. It is comfortable, familiar, and yielded a grand total of 120,499 identifications to date (109,354 of those are at species-level). I am proud of those numbers and have few regrets about the time spent to produce them. But change can be a good thing. And, I think it's high time for this one.
LE plants: 12,351 (12 months; 2019); 11,699 (6 months; 2020); 3,726 (June, 2020)
US Euphorbia: 15,215 (12 months; 2019); 9,592 (6 months; 2020); 2,206 (June, 2020)
World Anisophyllum: 3,908 (12 months; 2019); 2,358 (6 months; 2020); 395 (June, 2020)
Total: 31,474 (12 months; 2019), 2,622.8/month; 23,649 (6 months; 2020), 3,941.5/month; 6,327 (June, 2020), 226/day.

由使用者 nathantaylor nathantaylor2020年06月29日 05:01 所貼文 | 13 評論 | 留下評論


Plant highlights from the trip to Matador WMA and Gene Howe WMA

Recently, I went on a trip with some other iNaturalists to a couple of Wildlife Management Areas in the Rolling Plains of Texas: https://www.inaturalist.org/posts/36928-texas-panhandle-gathering-inaturalist-is-a-tool-of-engagement. We had a lot of fun and saw many interesting organisms. At Gene Howe, in particular, there were many species that are more common out east that I was unfamiliar with. By the end, I wondered if I should have told the folks from the DFW area, "if it looks ordinary or boring to you, then it's probably a good record for out here". My goal was to observe 300 plant species on this trip and I am at 330! I may get a couple more once I get some of the others to species, but I'm pretty happy with that. Overall, I'm at about 980 observations and will probably be a little over 1,000 when I get my blacklighting observations up. Thanks to @sambiology for putting all this together!

All of my observations can be seen here: https://www.inaturalist.org/observations?d1=2020-05-29&d2=2020-06-01&place_id=any&subview=grid&user_id=nathantaylor&verifiable=any
The highlights are as follows:

Nama stevensii

A species usually considered a gypsum endemic was found in the gypsum outcrops at Matador WMA. I had doubts at first, but I managed to find N. hispida in the general area as well and compare both species.

Townsendia texana

Though remarkably common in areas of the northern High and Rolling Plains, the species has a very limited distribution and is a neat regional plant:

Mentzelia spp.

On the trip, I was able to see all of the High/Rolling Plains Mentzelia species: M. reverchonii, M. nuda, M. oligosperma, M. decapetala (not in bloom), and M. strictissima (in abundance when I got home). From this, I was able to get a good sense of how to distinguish them all. M. nuda and M. strictissima are by far the most difficult and the characteristics given in FNA are misleading. I'll try to put together a more accurate key in the near future. I still didn't get enough material to know whether the two intergrade, but I do know that, if they intergrade, it occurs between Matador WMA and Lamesa, TX. Any observations in the area with rulers showing petal length and sepal shape of flowers in bud would really help with this. Also of interest, M. decapetala lacks the hairs that grab onto clothing, unlike most stickleafs.

Rubus pascuus

It keys well here, but the range is so far west that I have a hard time believing it. Nonetheless, it's an odd area to find a Rubus regardless of the species.

Phacelia robusta

BONAP lists this species as occurring in the Rolling Plains but Powell and Worthington list it as a Trans-Pecos endemic. While I am always inclined to believe Powell and Worthington over BONAP, I think the plants speak for themselves here. The plants can be huge under good conditions, though most individuals are small and stunted. The only thing that bugs me a little is the black seeds. P. robusta seeds are listed as reddish-brown in Powell and Worthington. Overall, I need to study this species in relation to P. integrifolia and P. texana as there seems to be significant variability in flower color and morphology, both of which are used as key characteristics. Most significantly, the distinction between tubular and funnelform flowers seem to be simply a matter of how long the corolla limb is. If short, the flower is tubular to funnelform, if long, it is campanulate.

Epipactis gigantea

This is the first orchid I have ever seen in the region. Though it wasn't found at any of the WMA's, it was quite a sight to behold! I have obscured the location as I'd really rather not have a lot of people know where this is (increased risk of poaching or disturbance).

Astragalus gracilis and cleistogamous A. lotiflorus

Though not that novel, it was my first time seeing A. gracilis and the cleistogamous populations of A. lotiflorus. The cleistogamous populations of A. lotiflorus are quite puzzling, not because the taxonomy doesn't make sense, but because I've never met a plant that has cleistogamous and chasmogamous populations. Plenty of plants produce both, but usually on the same plant as a way of hedging the bets under bad conditions. I could even see a scenario where some generations are cleistogamous and some are chasmogamous, but that's not what is observed. I have not once seen the two growing together which begs the question as to whether they should be considered the same instead of separate species. Regardless, it was nice to see them. I also saw A. lindheimeri, A. missouriensis, A. nuttalianus var. austrinus, A. mollissimus, and A. plattensis. I could have caught some others I had seen before on the way back, but I've documented those species well. Also, a species that looks similar to A. praelongus: Glycyrrhiza lepidota.

Oenothera coryi

Again, not at the WMAs, but another rare species. I was hoping to find it in fruit and I did. Many thanks to @amzapp for finding the location!

Other Oenothera species found on the trip included O. serrulata, O. hartwegii (at least three varieties), O. grandis, O. laciniata, O. triloba, O. engelmannii, O. albicaulis, O. rhombipetala, O. cinearea var. cinearea, O. suffulta, O. sinuosa, O. suffrutescens, and O. glaucifolia. A couple weren't in bloom. The observations I made on the trip of O. serrulata should help me figure out the distinctions between that species and O. berlandieri. So far, just the length of the style has been considered as the distinction. Also, some nice Schinia gaurae to go along with the members of sect. Gaura.

Ceanothus herbaceous

First time I've seen a Ceanothus in the region. Not at either of the WMAs.

Apocynum cannabinum

Though not rare or the first time I've seen it, it was the first time I saw it in flower which gives me some ability to understand the species in relation to the Monahans population which I believe to be a different species.

Argemone species

I documented at least two species on the trip and a couple of color variants of one (presumably A. polyanthemos). The group is complex and it seems that I encounter plant taxonomists are wondering about them whenever I am in the field with a group of them. I have not yet processed the material I gathered, but am hoping to write a key or guide on the subject once I get them figured out.


No trip report of mine would be complete without noting the Euphorbias. There wasn't much new, though I did get some photos of potential pollinators of E. albomarginata, a gall associate of E. fendleri, and a leaf miner and a leaf hopper on E. hexagona. Also, the leaves of E. serpens at Gene Howe were atypically elongated. Oblong leaves are not what I typically think of when I see E. serpens. Just more evidence that the species is a taxonomic complex waiting to be untangled. In total, I saw 14 species: E. hexagona, E. bicolor, E. spathulata, E. davidii, E. albomarginata, E. serpens, E. fendleri, E. lata, E. prostrata, E. stictospora, E. maculata, E. glyptosperma, E. geyeri var. geyeri, and E. missurica.

由使用者 nathantaylor nathantaylor2020年06月05日 16:54 所貼文 | 6 評論 | 留下評論


Using iNaturalist phenology to plan botany trips

Recently, I've been playing around with what can be done using the phenology annotation. It turns out, this information can be really helpful for planning a botany trip. To give an example, let's say you wanted to visit I-20 Wildlife Preserve in March to see what's blooming. All you would have to do is construct a link like the following, and you'll know exactly what to look out for: https://www.inaturalist.org/observations?month=3&place_id=64815&taxon_id=47126&term_id=12&term_value_id=13.

Now, this will obviously only work in places that have a decent iNaturalist presence and only if the observations are annotated. Regarding the former problem, iNaturalist continues to grow and as you, I, and the rest of the community explore, more and more places get mapped out. Regarding the latter problem, it is simple enough to add the phenology information in after the fact. Once you have observations with good annotation data, it's simply a matter of specifying the search terms to create the information in the above link. Let's walk through the steps (if the observations you're interested in are already annotated, skip steps 1 and 2).

1. Setting your parameters
a. Start by going to identify and specifying your taxon and area of interest (if your area of interest doesn't show up or work, you may have to find it under filters>more filters>place).
b. Click "filters".
c. Check "research grade".
d. Under "date observed", click month and then select the month you plan to take your trip.
e. Click "more filters".
f. Under "without annotations", select "plant phenology" (I usually leave it at "any", but it can be selected to only show observations that have not been annotated as "flowering" separately).
2. Adding phenology annotations
a. Click on an observation in flower or fruit.
b. Select the "annotation" tab.
c. To the right of "plant phenology", select one of the options (more than one option can be selected for this variable).
d. Go to another observation and repeat a-d.
e. Check the box next to "reviewed" and repeat steps a-d.

Once the observations are annotated, you can proceed to making use of the data.

3. Creating the right URL
a. If the observations of interest are already annotated and you didn't follow steps 1-2, start steps 1a-1e. If you followed steps 1-2, change "plant phenology" to "none" under "without annotations", uncheck the box next to "reviewed", and uncheck "research grade".
b. Under "with annotations", select "plant phenology" and select the condition for the structure you're interested in (e.g., "flowering" for flowers).
Here is an example using plants of I-20 Wildife Preserve that have been annotated as flowering: https://www.inaturalist.org/observations/identify?month=3&taxon_id=47126&place_id=64815&term_id=12&term_value_id=13
DO NOT CLOSE THIS TAB as you proceed to the next step.
4. Using that URL to get usable data
a. In a new tab, open the observation page (can be accessed by clicking the hyperlink or the "explore" tab).
b. Return to the tab with the identify page open and select every part of the URL after the word "identify". In the above example, it is: "?month=3&taxon_id=47126&place_id=64815&term_id=12&term_value_id=13".
c. Right click the text and select "copy" (or use ctr/cmnd c).
d. Go back to the observation page and add this extension to the URL that is already there by clicking after the URL, right clicking, and selecting "paste" (or use ctr/cmnd v).
e. Hit enter.

And that's all there is to it. Happy plant hunting! <!--

pg. 66
Species to exclude:
Species done 25 Mar 2020:
Machaeranthera tanacetifolia
Sphaeralcea coccinea
Dalea formosa
Tetraneuris scaposa
Oenothera suffrutescens
Oenothera hartweggii
Cactaceae (all reviewed; Jun-Dec, not unreviewed; &without_taxon_id=47903)
All unreviewed done
Excluded groups:
Ephedraceae, Pinales, Bryophyta, Polypodiopsida, Cactaceae

由使用者 nathantaylor nathantaylor2020年03月25日 18:46 所貼文 | 0 評論 | 留下評論


Hub to my stuff

由使用者 nathantaylor nathantaylor2019年04月26日 07:03 所貼文 | 1 評論 | 留下評論

Euphorbia resources and bibliography, full list

iNaturalist projects:
Euphorbia species of the United States
Euphorbia of Mexico
Sandmats of the World

iNaturalist journal posts (general):
Lists and project info:
Species list for the United States
List of species that have not been observed on iNaturalist yet
Project observation fields explained
Tracked statistics
Euphorbia, What to Photograph?
Tips on Harvesting and Photographing Seeds
Identification and taxonomy information:
What makes a good sandmat observation
Cyathium explained (Euphorbia PBI)
Cyathium explained in detail (journal post) and tips on cyathium dissection
Advanced Seed Morphology
Euhorbia PBI data portal (for finding species information including subgeneric taxa, nomenclatural information, and more)
Species commonly identified as Euphorbias
Euphorbia subgroups explained
Euphorbia marginata (Snow-on-the-Mountain) and E. bicolor (Snow-on-the-Prairie)
It's that time of year again: The spots of Spotted Spurge (Euphorbia maculata)
Section Nummulariopsis
Euphorbia albomarginata (Whitemargin Sandmat) and E. polycarpa (Smallseed Sandmat)
Euphorbia esula/virgata information (leafy spurges)
Detailed discussion
Discussion on E. saratoi
Flora of the Southern and Mid-Atlantic States (Weakley, draft 2015) (see pg. 675)
FNA treatment

General recomended external links:
Flora of North America
BONAP (for maps)
Euphorbia PBI
Euphorbia PBI species search
Tropicos (great way to find primary literature sources)
Biodiversity Heritage Library (great way to find primary literature sources)
GBIF (great way to find herbarium records)
Encyclopedia of life (often useful if you can find a good global map)
SEINet (great way to find herbarium records and photos)
Index herbariorum (useful in understanding what the herbarium abbreviations refer to)
Flora of the Southern and Mid-Atlantic States (Weakley, draft 2015) (see pg. 669)

Identification resources by Euphorbia subgroup
Section Alectoroctonum:
The eastern members of sect. Alectoroctonum
Euphorbia marginata (Snow-on-the-Mountain) and E. bicolor (Snow-on-the-Prairie)
Section Anisophyllum:
What makes a good sandmat observation
Euphorbia albomarginata (Whitemargin Sandmat) and E. polycarpa (Smallseed Sandmat)
It's that time of year again: The spots of Spotted Spurge (Euphorbia maculata)
The Weedy Species of Sandmats (Euphorbia sect. Anisophyllum) in Texas
Nathan Taylor's thesis: Explorations into Euphorbia sect. Anisophyllum (Euphorbiaceae) in the trans-Pecos region of Texas with a focus on the Fendleri Clade (I know, the title is very long)
Madagascar Species
Baja California Peninsula hub
Section Crepidaria:

Subgenus Esula:
Subgenus Esula explained
California Euphorbs of subgenus Esula
Texas Euphorbias, Subgenus Esula
Notes on cyathia with 5 glands
A few members of subgenus Esula sect. Helioscopia

Section Poinsettia:
Basic explaination of the Christmas Poinsettia
Poinsettia cyathia explaination

Section Nummulariopsis:
Section Nummulariopsis

State specific resources (not comprehensive and in progress)
Alabama Euphorbia species
City Spurges - Tucson
Jepson eFlora
California Euphorbs of subgenus Esula
City Spurges - San Diego
Florida Euphorbia species
Atlas of Florida Plants
Section Nummulariopsis
New Mexico:
The status of the genus Chamaesyce in New Mexico
Texas Euphorbia species list
The Weedy Species of Sandmats (Euphorbia sect. Anisophyllum) in Texas
City Spurges - DFW area
Sandmats (Euphorbia sect. Anisophyllum, previously Chamaesyce) of the Llano Estacado
Texas Euphorbias, the Tithymaloids
Nathan Taylor's thesis: Explorations into Euphorbia sect. Anisophyllum (Euphorbiaceae) in the trans-Pecos region of Texas with a focus on the Fendleri Clade (I know, the title is very long)

Outside North America
New Zealand Plant Conservation Network
NZ Flora (27 species listed)
European Euphorbia checklist - found here

*Note that this is taken directly from my annotated reference list and is incomplete (there are many more that I have referenced and several of those below I have not completely read, especially those in other languages). Also, many of the citations are incomplete or are not consistantly formated. It is likely too long to be of much use here, but at least it can be referanced if anyone wonders where I am getting my information.

Master's Thesis: Explorations into Euphorbia sect. Anisophyllum (Euphorbiaceae) in the trans-Pecos region of Texas with a focus on the Fendleri Clade
Felger, R.S., S. Rutman, & N.C. Taylor. 2015. Ajo Peak to Tinajas Altas: A flora of southwestern Arizona. Part 13. Eudicots: Euphorbiaceae. Phytoneuron 2015:1–65..
Taylor, N.C. & M. Terry. 2015. Euphorbia abramsiana (Euphorbiaceae): New to Texas. Phytoneuron 2015-24:1–7. ISSN 2153 733X
Taylor N.C. & M. Terry. 2016. Euphorbia cryptorubra (Euphorbiaceae), a new species in Euphorbia subgenus Chamaesyce section Anisophyllum from Texas, U.S.A. and Chihuahua, Mexico. Journal of the Botanical Research Institute of Texas 10:1–9.
Atha, D., Levine, E., and Taylor, N. 2018. First report of Euphorbia hypericifolia (Euphorbiaceae) for New York state. Phytoneuron 2018-74: 1–4.
Mickley, J.G. and Taylor, N. In progress. Occurrence of Thymeleaf Sandmat Euphorbia serpillifolia Persoon (Euphorbiaceae) in Vermont.

Bentham, G. 1844. The botany of the voyage of H.M.S. Sulphur. Smith, Elder and Co., London, UK. http://www.biodiversitylibrary.org/item/15490
Berry, P.E., V. Steinmann, & Y. Yang. 2011. Proposal to conserve the name Euphorbia acuta Engelm. against E. acuta Bellardi ex Colla (Euphorbiaceae). Taxon 60:603–604.
Berry, P.E., J.A. Peirson, J.J. Morawetz, V.W. Steinmann, R. Riina, Y. Yang, D. Geltman, & N.I. Cacho. 2016. Euphorbia. Flora of North America Editorial Committee, eds. Flora of North America North of Mexico. Vol. 12. New York and Oxford.
Blake, S.F. 1922. New plants from Guatemala and Honduras. Contributions from the United States National Herbarium. Vol. 24, part 1.
Boissier, E. 1860. Centuria Euphorbiarum. Société de physique et d'histoire naturelle de Genève.
Boissier, E. 1862. Euphorbia sect. Anisophyllum. In A.P. de Candolle [ed.], Prodromus systematis naturalis regni vegetabilis, vol. 15, part 2, 11–52. Victor Masson & Fils, Paris, France.
Brown, N.E. 1911. Euphorbia. In Flora of tropical Africa vol. 6. [Authors for Euphorbiaceae: N.E. Brown, J. Hutchinson, & D. Prain]
Brown, N.E. 1925. Euphorbia. In Flora Capensis vol. 5, section 2. [Authors for Euphorbiaceae: N.E. Brown, J. Hutchinson, & D. Prain]
Burch, D. 1965. A taxonomic revision of the genus Chamaesyce (Euphorbiaceae) in the Caribbean. Ph.D. dissertation, University of Florida, Gainesville, Florida, USA.
Burch, D. 1965. Two species of Chamaesyce (Euphorbiaceae) new to the United States. Rhodora 67:185–186.
Burch, D. 1966. The application of the Linnaean names of some New World species of Euphorbia subgenus Chamaesyce. Rhodora 68:155–166.
Burch, D. 1966. Two new species of Chamaesyce (Euphorbiaceae), new combinations, and a key to the Caribbean members of the genus. Annals of the Missouri Botanical Garden 53:90–99.
Burch, D. 1969. Notes on the Galapagos Euphorbieae (Euphorbiaceae). Annals of the Missouri Botanical Garden 56:173–178.
Burger, W. & M. Huft. 1995. Flora Costaricensis: Family #113 Euphorbiaceae. Fieldiana: Botany No. 36.
Carr, W.R. & M.H. Mayfield. 1993. Chamaesyce velleriflora (Euphorbiaceae) new to Texas. Sida 15:550–551.
Carter, S. 1979. Some new Euphorbia species from East Africa. Kew Bulletin 35:413–421. http://www.jstor.org/stable/4114592
Carter, S. 1983. New taxa and notes on herbaceous species of Euphorbia from East and Northeast Africa. Kew Bulletin 39:643–652. http://www.jstor.org/stable/4108605
Carter, S. 1989. New taxa and taxonomic changes amongst herbaceous Euphorbia species from southern tropical Africa. Kew Bulletin 45:327–337. http://www.jstor.org/stable/4115690
Carter, S. & L.C. Leach. 2001. Euphorbiaceae part 2. Flora Zambesiaca Vol. 9 part 5.
Carter, S. & A.R. Smith. 1988. Euphorbiaceae (Part 2). Flora of Tropical East Africa. Royal Botanic Gardens, Kew, Richmond, England.
Correll, D. S. & M. C. Johnston. 1970. Manual of the vascular plants of Texas. Texas Research Foundation, Renner, Texas.
Croizat, L. 1943. Novelties in American Euphorbiaceae. Journal of the Arnold Arboretum 24:165–189.
Croizat, L. 1945. “Euphorbia chamaesyce” in the United States. Bulletin of the Torrey Botanical Club 72:312–318.
Farwell, O.A. 1936. Euphorbia pilulifera in Michigan. Rhodora 38:331–332.
Fawcett, W. & A.B. Rendle. 1910. Flora of Jamaica: Euphorbia. William Clowes and Sons, London.
Felger, R.S., S. Rutman, & N.C. Taylor. 2015. Ajo Peak to Tinajas Altas: A flora of southwestern Arizona. Part 13. Eudicots: Euphorbiaceae. Phytoneuron 2015:1–65.
Fernald, M.L. 1936. Dates of publication of Rydberg’s Flora of the Rocky Mountains and adjacent plains. Rhodora 38:329–331. Only cited here because of another citation.
Florence, J. 1996. Gallicae Polynesiae florae Praecursores. 1. Nouveautés taxonomiques dans les Euphorbiaceae, Piperaceae et Urticaceae. Bulletin du Muséum National d'Histoire Naturelle, Section B, Adansonia. sér. 4, Botanique Phytochimie 18:239–274.
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Bauer, G. S.N. Gorb, M.C. Klein, A. Nellesen, M. Tapavicza, & T. Speck. 2014. Comparative study on plant latex particles and latex coagulation in Ficus benjamina, Campanula glomerata and three Euphorbia species. Plos One 9:e113336. http://dx.doi.org/10.1371/journal.pone.0113336
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Yang, Y. & P. Berry. 2011. Phylogenetics of the Chamaesyce Clade (Euphorbia, Euphorbiaceae): Reticulate evolution and long-distance dispersal in a prominent C4 lineage. American Journal of Botany 98:1486–1503. doi:10.3732/ajb.1000496
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Zimmermann, N.F.A., C.M. Ritz, & F.H. Hellwig. 2010. Further support for the phylogenetic relationships within Euphorbia L. (Euphorbiaceae) from nrITS and trnL–trnF IGS sequence data. Plant Systematics and Evolution 286:39–58. doi:10.1007/s00606-010-0272-7
Aldhebiani, A. & S. Jury. 2013. Anatomical studies on the genus Euphorbia L. Saudi Arabia (Subgenera: Triucalli, Ermophyton, Esula and Chamaesyce). International Research Journal of Plant Science. 4:168–191. Several good references.
Batanouny, K.H., W. Stichler, & H. Ziegler. 1991. Photosynthetic pathways and ecological distribution of Euphorbia species in Egypt. Oecologia 87:565–569.
Christin, P.A., T.L. Sage, E.J. Edwards, R.M. Ogburn, R. Khoshravesh, & R.F. Sage. 2010. Complex evolutionary transitions and the significance of C3–C4 intermediate forms of photosynthesis in Molluginaceae. Evolution 65:643–660.
Kadereit, G., K. Bohley, M. Lauterbach, D.T. Tefarikis, & J.W. Kadereit. 2017. C3–C4 intermediates may be of hybrid origin – a reminder. New Phytologist 215:70–76.
Kakkar, L. & G.S. Paliwal. 1972. Studies on the leaf anatomy of Euphorbia: V. Epidermis. Proceedings of the Indian National Science Academy Part B Biological Sciences 40:55–67.
Webster, G.L., W.V. Brown, & B.N. Smith. 1975. Systematics of photosynthetic carbon fixation pathways in Euphorbia. Taxon 24:27–33.
Herbst, D. 1971. Disjunct foliar veins in Hawaiian Euphorbias. Science 171:1247–1248.

Asgarpour, R., R. Ghorbani, M. Khajeh-Hosseini, E. Mohammadvand, & B.S. Chauhan. 2015. Germination of Spotted Spurge (Chamaesyce maculata) seeds in response to different environmental factors. Weed Science 63:502–510.
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Ernst, M., O.M. Grace, C.H. Saslis-Lagouakis, N. Nilsson, H.T. Simonsen, & N. Rønsted. 2015. Global medicinal uses of Euphorbia L. (Euphorbiaceae). Journal of Ethnopharmacology 196:90–101.
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Porcher, R.D. & D.A. Rayner. 2002. A guide to the wildflowers of South Carolina. Columbia.
Papers on organisms found on Euphorbia:
Evans, G.A. & A. Polaszek. 1997. Additions to the Encarsia parasitoids (Hymenoptera: Aphelinidae) of the Bemisia tabaci-complex (Hemiptera: Aleyrodidae). Bulletin of Entomological Research 87:563–571. Larvae on Chamaesyce leaves.
Fischer, E. W. Lobin, & J. Mutke. 2011. Striga barthlottii (Orobanchaceae), a new parasitic species from Morocco. Willdenowia 41:51–56. On succulent Euphorbias.

Keil, D.J. 1976. Chromosome numbers for Euphorbia (Euphorbiaceae) from western North America. Madroño 23:405–408.
Urbatsch, L.E., J.D. Bacon, R.L. Hartman, M.C. Johnston, T.J. Watson Jr., & G.L. Webster. 1975. Chromosome numbers for North American Euphorbiaceae. American Journal of Botany 62:494–500.

Brown, R. 1818. Observations on the natural family of plants called Compositae. Transactions of the Linnean Society of London 12:76–142.
Croizat, L. 1936. On the classification of Euphorbia. I. How important is the cyathium? Bulletin of the Torrey Botanical Club 63:525–531.
Narbona, E., P.L. Ortiz, & M. Arista. 2002. Functional andromonoecy in Euphorbia (Euphorbiaceae). Annals of Botany 89:571–577. Not Read!
Prenner, G. & P.J. Rudall. 2007. Comparative ontogeny of the cyathium in Euphorbia (Euphorbiaceae) and its allies: Exploring the organ, flower, inflorescence boundary. American Journal of Botany 94:1612–1629.
Prenner, G., N.I. Cacho, D. Baum, & P.J. Rudall. 2010. Is LEAFY a useful marker gene for the flower-inflorescence boundary in the Euphorbia cyathium? Journal of Experimental Botany 62:345–350.
Wheeler, L.C. 1936. Revision of the Euphorbia polycarpa group of the Southwestern United States and adjacent Mexico, a preliminary treatment. Bulletin of the Torrey Botanical Club 63:397–416, 429–450. http://www.jstor.org/stable/2480946

由使用者 nathantaylor nathantaylor2019年04月26日 06:41 所貼文 | 0 評論 | 留下評論


Texas Euphorbias, Subgenus Esula

I finally went through all the Texas Euphorbias including a group that has given me some trouble in the past: subgenus Esula. Here are the important characteristics that I came up with that roughly goes from easiest to separate to most difficult or grouped by similar species. If not mentioned, assume horned glands, smooth fruits, and entire leaves. For terminology information, please read here.

E. lathyris: Leaves clearly opposite, forming an X shaped pattern going up the stem; plants bluish-green.

E. spathulata: Serrated leaves, pleiochasial bracts ovate (broadest near base), dichasial bracts essentially deltoid (broadest at base), no horn-like appendages on the oval glands, and warty fruits

Third photo: E. spathulata: left; E. texana: right. Source observation here

E. texana: Just like E. spathulata but with smooth fruits and elongated, spathulate pleiochasial bracts (broadest at apex), and oval dichasial bracts (broadest near middle).

Source observation here

E. helioscopia: Like E. texana but typically with around 5 pleiochasial branches instead of 3 (the main branches of the inflorescence).

E. peplus: Winged fruits.

Source observation here and here.

E. roemeriana: Partially fused dichasial bracts (the bracts that are held in pairs), restricted to the Balcones Escarpment in Central Texas (the vicinity of Austin to the Pecos River).

Source observation here

E. ouachitana: Partially fused dichasial bracts (the bracts that are held in pairs); in TX, restricted to the NE corner.

E. brachycera: Large perennial plants usually with acuminate triangular-ovate bracts; main leaves note significantly broader at apex than base, not linear.

Source observation here

E. peplidion: Dichasial bracts broadly lanceolate to lanceolate with acute apices and non-truncate bases.

Source observation here

E. longicruris: Dichasial bracts imbricate notably asymmetric with the ventral half extended, generally distinctly reniform, generally strongly ascending, apices rounded, bases cordate and overlapping if spread; fruits with two raised areas along the keels (not wings) similar to E. peplus.

Source observation here

E. austrotexana: Leaves narrow, linear to oblanceolate or narrowly lanceolate.

E. falcata: Leaves acute, dichasial bracts strongly acuminate bases paler than rest of bract.

E. tetrapora: Dichasial bracts essentially symmetric or slightly asymmetric, generally subdeltoid, generally spreading or weakly ascending, apices typically mucronate, bases generally truncate to subcordate; stems erect, unbranched at the base; fruits with two raised areas along the keels (not wings) similar to E. peplus.

Source observation here

E. helleri: Dichasial bracts mucronate or not, sometimes abruptly narrowing at the middle with a rounded apex; stems ascending, branched at the base; lower leaves often notably emarginate, leaves except dichasial bracts spathulate or oblanceolate.

Source observation here

I'd like to note that E. austrotexana has not been observed on iNaturalist and E. lathyris, E. ouachitana, nor E. helioscopia have been observed for Texas if anyone is interested in hunting them down. By the way, I continually update a list of all the species not observed in the US on iNaturalist here.

The records of E. ouachitana and E. falcata are not recorded anywhere else. E. falcata is based on the observation here and E. ouachitana is based on a paper documenting E. commutata for Texas. The taxonomy was revised here and the photos showing E. commutata in Texas are actually of E. ouachitana.

ID notes on E. peplus, E. longicruris, and E. tetrapora: I have had some difficulty distinguishing these three in the past. They key in very different places making it difficult to ascertain the essence of their differences (especially with E. longicruris as distinctive as the imbricate bracts are and how problematic it can be when considering things like etiolation). Since creating this, the distinctions have been updated and should reflect a more consistent understanding of the species.

Comparison of the fruits of E. peplus (left) and E. longicruris (right):

Other annual members of subgenus Esula across the US:

E. commutata: Distributed throughout the Eastern United States as far southwest as Oklahoma, Arkansas, and Louisiana. Potentially expected for Texas.

E. georgiana : Restricted to Georgia. Other annual related species potentially in state: E. spathulata and E. commutata.

E. crenulata: Distjuctly distributed in California, Oregon, Colorado, and New Mexico. Other annual related species potentially in states: E. spathulata.

E. alta: Restricted to Arizona and New Mexico. Other annual related species potentially in states: E. spathulata.

E. platyphyllous: Introduced throughout much of the Eastern United States as far southwest as Tennessee.

E. exigua: Introduced to California, West Virginia, and New York.

Original publication for E. austrotexana

由使用者 nathantaylor nathantaylor2019年04月15日 20:31 所貼文 | 18 評論 | 留下評論


A quick trip to California

I just got back from a rather quick and intensive trip to California and figured it would be fun to write up some of the things that happened in this journal post.

6 Mar: To start the day, my parents and I drove from the eastern edge of AZ (TX Canyon rest stop) to CA. I had contacted Dr. Victor Steinmann a few days prior and I was going to meet him today. Dr. Steinmann had offered to take me to a population of Euphorbia jaegeri (a really rare California endemic) off of I-10 out near Joshua Tree National Park. On the way there, we stopped near Phoenix, AZ and I saw what may be the narrowest leaf forms of E. maculata I've ever seen. Not a major find, but a fun find nonetheless. A few hours later, we met with Dr. Steinmann. He and I carpooled to the base of a canyon where E. jaegeri was located. Nearly immediately after getting out of the car, I managed to impale myself on Cylindropuntia ramosissima (serves me right for not paying attention in the desert). The wildflowers were wonderful. I recognized few of the genera and even fewer species. A full list can be found here. After climbing and talking extensively about Euphorbia, we found what we were looking for. A couple of the E. jaegeri plants were a foot across or more! It took more searching and climbing, but we eventually found a single immature fruit. Most of the plants had no cyathia. When we got back, we took a quick trip to Joshua Tree NP and saw all the wildflowers in bloom. Perhaps the highlight was seeing Tetracoccus hallii which used to be in Euphorbiaceae but is now a member of Picrodendraceae. A full list can be found here.
At some point in the field, Dr. Jon Rebman replied to my email asking if I could come by the herbarium at the San Diego Natural History Museum.

7 Mar: In the morning, my parents and I drove to San Diego and went to the herbarium at the San Diego Natural History Museum. I got a ton of work done on one of the more complicated Euphorbia problems in Baja California. I nearly got as much done as I was expecting to but didn't get anywhere near as much as I wanted to. There are just too many species complexes that need studying. Perhaps the most interesting realization is just how bad of a catch-all group E. serpillifolia really is. There always seems to be more work to do in Euphorbia!

8 Mar: Not much to report here. I got a little time to explore a nearby park and a full list of things I found can be seen here.

From this point on, I was preoccupied essentially the entire time with non-botany stuff. I managed to find a lifer and a few other little interesting things, but nothing like what I found those three days. In particular, Euphorbia peplus is a common weed throughout much of CA, but I have only gotten to see it once (in El Paso). It was nice to get to see the many plants of it growing in person. So naturally, I ended up adding photos of the two most commonly observed species on iNaturalist and they will get lost in the mess. :-) Also, to those who may have wanted to see me when I was in the area, I apologize for not reaching out. I would have loved to make more of the trip, but I just didn't have the time. Most of my observations other than those mentioned above were taken quickly between locations and even the stops above were much quicker than I would have preferred.

由使用者 nathantaylor nathantaylor2019年03月17日 19:12 所貼文 | 5 個觀察記錄 | 3 評論 | 留下評論